Allenylphosphonates/allenylphosphine oxides as intermediates/precursors for intramolecular cyclization leading to phosphorus-based indenes, indenones, benzofurans, and isochromenes

Article abstract of DOI:10.1021/jo300705f

Utilizing internally available functional groups, a simple protocol for the efficient synthesis of phosphorus-based indenes, indenones, benzofurans, and isochromenes via intramolecular cyclization of allene intermediates/precursors is generated; the latter intermediates/precursors are conveniently obtained through aldehyde-, alkylidene-, and hydroxyl-functionalized propargyl alcohols and P^III-Cl precursors. The structures of key products have been unequivocally confirmed by X-ray crystallography.

Full text of DOI:10.1021/jo300705f

Article
pubs.acs.org/joc
Allenylphosphonates/Allenylphosphine Oxides as Intermediates/
Precursors for Intramolecular Cyclization Leading to Phosphorus-
Based Indenes, Indenones, Benzofurans, and Isochromenes
K. V. Sajna and K. C. Kumara Swamy*
School of Chemistry, University of Hyderabad, Hyderabad 500 046, A. P., India
S
* Supporting Information
ABSTRACT: Utilizing internally available functional groups,
a simple protocol for the efficient synthesis of phosphorus-
based indenes, indenones, benzofurans, and isochromenes via
intramolecular cyclization of allene intermediates/precursors is
generated; the latter intermediates/precursors are conveniently
obtained through aldehyde-, alkylidene-, and hydroxyl-
functionalized propargyl alcohols and PIII−Cl precursors.
The structures of key products have been unequivocally
confirmed by X-ray crystallography.
Chart 1. Heterocycles/Polycycles Prepared via
Functionalized Propargyl Alcohols5
INTRODUCTION
■
Allenes are useful precursors for the construction of key
building blocks that are present in many natural products and
pharmaceutically important molecules.1,2 In the past decade, a
vast number of polycycles and heterocycles have been
synthesized via intramolecular or intermolecular cyclization/
cycloaddition reactions by employing the functionalized allene
derivatives.3,4 For example, allenes can undergo cyclization
reactions with nucleophiles having an additional functionality
(e.g., −I, −Br, −CHO) to yield a diverse range of
heterocycles.4a−e These reactions can be accomplished by
transition-metal, Lewis acid, or Lewis base catalyzed conditions.
Our research group has reported the synthesis of phosphono-
benzofurans,4a,c -pyrazoles,4b -chromenes,4d -oxindoles,4e and
multiply substituted furans4f from inexpensive allenes under
Lewis acid, transition-metal, or base catalyzed conditions. In
addition to these, very recently, we reported a novel synthesis
of benzazipines, N-hydroxyindoles, and polycycles (compounds
1−5; Chart 1) via allene intermediates;5 the key to such an
astounding variety of products is the functionalized allene
intermediate (6). Encouraged by these results, and as a part of
our studies focused toward the synthesis of novel functionalized
allenylphosphonates/allenylphosphine oxides6 for the develop-
ment of cyclization reactions, we became interested in
obtaining the propargyl alcohols 7−23 containing an
alkylidene, a formyl, or a hydroxyphenyl group (Chart 2).7
We also wish to point out that the amenability of 31P NMR has
significantly aided us in readily analyzing the course of such
reactions and we believe that this knowledge can be gainfully
employed in the case of non-phosphorylated allenes. In this
context, we wish to disclose the formation/synthesis of different
types of polycyclic and heterocyclic molecules by systematic
alteration of inexpensive propargyl alcohols and PIII−Cl
precursors. We should note that the normally expected
products in such reactions are allenes.6
RESULTS AND DISCUSSION
■
We first focus on two new intramolecular ene reactions via
allenic intermediates exhibited by the alkylidene-based
propargyl alcohols 7−11 and the aldehyde-based propargyl
Received: April 6, 2012
© XXXX American Chemical Society
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Chart 2. Functionalized Propargyl Alcohols 7−23 Used in
the Present Study
Scheme 1. Synthesis of Phosphono-Indenes 26−34
alcohols 12 and 13, respectively. These will be followed by
intramolecular cyclizations assisted by a base (Et3N) or Lewis
acid (ZrCl4). We believe that these represent a class of
reactions that have been previously unexplored.
(i). Reaction of Alkylidene-Based Propargyl Alcohols
7−11 with PIII−Cl Compounds 24 and 25: Synthesis of
Phosphono-Indenes 26−34 via an Intramolecular Ene
Reaction. Our initial aim was to synthesize the alkylidene-
based allenylphosphonate I by using the propargyl alcohol 7
and PIII−Cl precursor 24 under the conditions mentioned in
Scheme 1. To our surprise, however, we isolated the indene
derivative 26 rather than the allene. The structure has been
proven by single-crystal X-ray crystallographic studies (see the
Supporting Information). We extended this work by using the
propargyl alcohols 8−10 to obtain the products 27−29 in good
yields (Scheme 1). By using the same method when propargyl
alcohol 11 was treated with PIII−Cl precursor 24, we obtained
product 30. Products 31−34, similar to 26−29, were formed
when the PIII−Cl precursor 25 (containing an eight-membered
ring; see Scheme1) was treated with the propargyl alcohols 7−
10.
Scheme 2. Intramolecular Ene Pathway for the Formation of
26−30 (and 31−34)
On the basis of previous studies,6 it is reasonable to assume
that the most viable primary intermediate in the above reaction
is the allene I (Scheme 2). An intramolecular ene8 reaction
leads to species II, which on subsequent proton migration
furnishes the final products 26−34.
(ii). Reaction of Aldehyde Functionalized Propargyl
Alcohols 12 and 13 with PIII−Cl Precursors 24/35:
Formation of Phosphono-Indenone Derivatives 36−39.
Encouraged by the above results, we thought that by employing
the aldehyde-based propargyl alcohol 12 we could generate a
new cyclic system. In order to explore this, we treated the
propargyl alcohol 12 with the PIII−Cl precursor 24 (Scheme 3)
by a procedure similar to what was described above. In the 31P
NMR spectrum, the reaction mixture showed only one peak at
δ 19.8, which did not correspond to the allene (δ 6.5−8.0).
After isolation, we surmised that this synthetic route afforded
the unexpected indenone derivative 36 (on the basis of
spectroscopic and analytical data) instead of the expected
allene (vide infra). Thus, a simple and inexpensive route to
indenones has been generated. The presence of the α-P−CH
proton, as revealed by a doublet at δ 4.56 with a J(P−H) value
of 23.2 Hz, indicates that the compound is allylphosphonate
and not a vinylphosphonate. The scope of the reaction was
then extended by using the PIII−Cl precursor 35. In all the
cases the final indenones 36−39 (Scheme 3) were obtained in
good yields. The structure of product 38 was confirmed by X-
ray crystallography (see the Supporting Information). The
Me2CC distance of 1.337(4) Å indicates a double bond
between these two atoms, as depicted in the structural drawing
(Scheme 3).
The rather unprecedented formation of phosphono-inden-
one derivatives 36−39 can be explained by the pathway shown
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Scheme 3. Synthesis of Phosphono-Indenone Derivatives
36−39
Scheme 5. Synthesis of Allenes 40−55
Scheme 4. Intramolecular Ene Pathway for the Formation of
36−39
Scheme 6. Reported Method11 for the Synthesis of
Compound 56
in Scheme 4. The initially formed allene intermediate III can
undergo an intramolecular ene reaction leading to a cyclic
intermediate (IV).8 H migration in intermediate IV then
afforded the enol intermediate V, which on subsequent
tautomerization gave rise to the final product 36 (or 37−39).
(iii). Cyclization Reaction of Allenes 46−51 Possessing
a 2-Hydroxyphenol Side Group: Synthesis of 1,2-
Disubstituted Benzofuran Derivatives 56−61. Intermo-
lecular nucleophilic addition of amines, phenols, and thiols to
allenylphosphonates has been fairly well explored.3a,9,10 Also,
having realized the potential of keeping an ortho functionality
in aryl-substituted propargyl alcohols in the reactions discussed
above, we turned our attention to the α-MOM-protected
hydroxyphenyl allenylphosphine oxides 40−45, which were
synthesized readily by standard routes.6 The hydroxyphenyl-
substituted allenes 46−51 required for cyclization were then
prepared from the hydrolysis of allenes 40−45 (Scheme 5;
although the corresponding allenes with a benzylic alcohol
residue from 52−55 may also be prepared in an analogous
manner, this step was not required in the present study (vide
infra)). In order to fully authenticate the multifunctional nature,
one of these compounds (46) was characterized by single-
crystal X-ray crystallography (see the Supporting Information).
We then focused on the intramolecular nucleophilic-addition
reactions of these functionalized allenes.
in excellent yield (95%; Table 1). The spectroscopic data are
consistent with those reported in the literature; however, the
literature route requires a large number of steps, as shown in
Scheme 6.11 Hence, we developed our simpler route by using
various allenylphosphine oxides 47−51 that lead to various
substituted benzofuran derivatives 57−61 (Table 1). The X-ray
structure of the product 61 (see the Supporting Information)
conclusively proved the formation of the benzofurans. It may be
noted that the phenolic proton could have moved to the α-
carbon (with respect to phosphorus) also, but formation of the
benzofuran system is favored in the present case.
(iv). Formation of 3,4-Disubstituted Isochromenes
62−65 (via ZrCl4 Catalysis) and Halobenzyl Products 66
and 67 from MOM-Protected Allenes 52−55. Inspired by
the above results, and in order to extend the nucleophilic-
addition reaction strategy, we chose the benzyloxy-MOM-
protected allenes 52−55. Since our strategy was to obtain the
cyclized product, we made an attempt to deprotect allene 52 by
employing the Lewis acid ZrCl4.12 Thus, we treated allene 52
with ZrCl4 (0.5 mol equiv) in methanol under reflux over a
period of 2 h. To our delight, this reaction straightaway ended
We first explored the intramolecular cyclization of 46 under
basic (Et3N) conditions. Although allene 46 did not cyclize in
the presence of triethylamine (1 mol equiv) at room
temperature, we succeeded in obtaining the expected
benzofuran 56 when the mixture was heated under reflux for
2 h. This reaction was clean, and the product 56 was obtained
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Table 1. Synthesis of 2,3-Disubstituted Benzofurans 56−61
Table 2. Synthesis of Isochromenes 62−65 via Allenes 52−
a
a
via Allenes 46−51
55
a
Reaction conditions: allene (1.0 mmol), ZrCl4 (0.5 mol equiv),
b
MeOH (2 mL), reflux for 2−3 h. Yield of the isolated product.
Scheme 7. Formation of Allylic Alcohols 66 and 67
a
Reaction conditions: allene (1.0 mol equiv), Et3N (1.0 mol equiv),
b
THF (2 mL), reflux for 1−2 h. Yield of the isolated product.
up with a nucleophilic addition−cyclization product, isochro-
mene 62 (Table 2) in one step and there was no deprotected
allene, thus alleviating the additional step. We explored this
reaction further by employing various γ-dialkyl-substituted
allenylphosphine oxides 53−55 to obtain 3,4-disubstituted
isochromenes 63−65 in excellent yields (Table 2). For further
structural confirmation, one of these compounds (63; Table 2,
entry 2) was subjected to single-crystal X-ray crystallographic
analysis (see the Supporting Information).
In place of ZrCl4, when we used concentrated HX (X = Br,
Cl) /EtOAc under reflux conditions, we obtained the
noncyclized water-added benzylic halides 66 and 67 (Scheme
7; see the Supporting Information for the X-ray structure of
66). Although this leads to synthetically useful allylic alcohols,
since this was not the theme of the present work, we have not
explored this reaction further.
CONCLUSIONS
■
New cyclization reactions via an intramolecular ene-type or
nucleophilic addition/cyclization pathway by employing
functionalized propargyl alcohols and PIII−Cl precursors have
been discovered. The α-(2-formyl/2-alkylidene)-phenyl-based
allenes formed in situ gave indane-based compounds via an
ene-type pathway, whereas the α-(2-hydroxyphenyl)- or α-((2-
methylhydroxy)phenyl)-based allenes afforded the benzofurans
or isochromenes via a nucleophilic addition/cyclization route.
Thus, this chemistry provides a convenient access to a variety of
indenes, indenones, benzofurans, and isochromenes from
inexpensive functionalized propargyl alcohols and presents a
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(br, 1H), 3.79 and 3.84 (2 s, 6H), 7.29−7.49 (m, 4H), 8.24 (s, 1H);
13C NMR (100 MHz, CDCl3) δ 23.4, 25.2, 39.9, 52.6, 52.9, 69.2, 81.6,
100.1, 124.4, 126.6, 127.4, 128.3, 130.1, 132.5, 134.7, 141.7, 164.4,
166.8; LC/MS m/z 342 [M]+. Anal. Calcd for C20H22O5: C, 70.16; H,
6.48. Found: C, 70.15; H, 6.58.
substantial extension of the known synthetic routes to these
types of derivatives.
EXPERIMENTAL SECTION
■
Compound 10. This compound was prepared by using 2-(2-
bromobenzylidene)malonic acid diethyl ester (1.18 g, 3.6 mmol) and
1-ethynyl-1-cyclohexanol (0.54 g, 4.3 mmol) and purified by column
chromatography using an ethyl acetate/hexane (3/7) mixture as the
eluent: yield 0.76 g (67%, yellow oil); IR (neat, cm−1) 3461, 2936,
(i). General Comments. Solvents were dried according to known
methods as appropriate.13 1H, 13C, and 31P NMR spectra (1H, 400 or
500 MHz; 13C, 100 or 125 MHz; 31P, 162 MHz) were recorded using
a 400 or 500 MHz spectrometer in CDCl3 with shifts referenced to
SiMe4 (δ 0) or 85% H3PO4 (δ 0). IR spectra were recorded on an
FTIR spectrophotometer. Melting points were determined by using a
local hot-stage melting point apparatus and are uncorrected. Elemental
analyses were carried out on a CHN analyzer. Mass spectra were
recorded using LC-MS and HRMS equipment.
1
1730, 1632, 1449, 1379, 1254, 1065; H NMR (400 MHz, CDCl3) δ
1.23 and 1.34 (2 t, J = 7.0 Hz, 6H), 1.53−1.76 (m, 8H), 2.05 (br, 2H),
2.37 (br, 1H), 4.26−4.33 (m, 4H), 7.27−7.35 and 7.45−7.49 (2 m,
4H), 8.20 (s, 1H); 13C NMR (100 MHz, CDCl3) δ 13.9, 14.2, 23.4,
25.2, 39.9, 61.7, 69.2, 81.7, 99.8, 124.2, 127.5, 127.6, 128.3, 129.9,
132.5, 134.9, 140.9, 164.0, 166.4; LC/MS m/z 370 [M]+. Anal. Calcd
for C22H26O5: C, 71.33; H, 7.07. Found: C, 71.25; H, 7.18.
Compound 11. This compound was prepared by using (E or Z)-
ethyl 2-(2-bromobenzylidene)-3-oxobutanoate (0.50 g, 1.7 mmol) and
2-methylbut-3-yn-2-ol (0.17 g, 2.0 mmol) and purified by column
chromatography using an ethyl acetate/hexane (3/7) mixture as the
eluent: yield 0.25 g (50%, yellow oil); IR (neat, cm−1) 3449, 2982,
1703, 1620, 1368, 1248, 1059; 1H NMR (500 MHz, CDCl3) δ 1.35 (t,
J = 7.3 Hz, 3H), 1.68 (s, 6H), 2.31 (s, 3H), 2.48 (br, 1H), 4.30−4.34
(m, 2H), 7.29−7.37 (m, 3H), 7.48−7.49 (m, 1H), 8.14 (s, 1H); 13C
NMR (100 MHz, CDCl3) δ 14.2, 31.3, 31.4, 61.7, 65.7, 79.6, 101.0,
124.0, 128.3, 128.6, 129.9, 132.5, 134.8, 135.0, 139.0, 164.4, 203.0;
LC/MS m/z 301 [M + 1]+. Anal. Calcd for C18H20O4: C, 71.98; H,
6.71. Found: C, 71.83; H, 6.62.
Compound 13. This compound was prepared by using 2-
bromobenzaldehyde (1.59 g, 8.6 mmol) and 1-ethynylcyclohexanol
(1.28 g, 10.2 mmol). It was isolated by using an ethyl acetate/hexane
(3/7) mixture as the eluent: yield 1.29 g (66%, yellow oil); IR (neat,
cm−1) 3410, 2965, 1696, 1595, 1389, 1273, 1073; 1H NMR (400
MHz, CDCl3) δ 1.30−2.05 (m, 10H), 2.72 (br, 1H), 7.41−7.52 (m,
3H), 7.87−7.89 (m, 1H), 10.50 (s, 1H); 13C NMR (100 MHz,
CDCl3) δ 23.4, 25.1, 39.9, 69.2, 79.9, 100.3, 126.5, 127.3, 128.6, 133.4,
133.8, 135.9, 191.8; LC/MS m/z 229 [M + 1]+. Anal. Calcd for
C15H16O2: C, 78.92; H, 7.06. Found: C, 78.85; H, 7.12.
(ii). Preparation of Propargylic Alcohol and PIII−Cl Pre-
cursors. The propargylic precursors 7−23 were synthesized by
Sonogashira coupling reactions of the respective iodo/bromo
substrates (2-(2-bromobenzylidene)malonic acid dimethyl (diethyl)
esters were prepared according to the literature procedure14 and 1-
iodo-2-methoxymethoxybenzene15a and 1-iodo-2-methoxymethoxyme-
thylbenzene15b were prepared by treating the corresponding alcohols
with chloromethyl methyl ether in the presence of sodium hydride
(NaH) in THF15) with propargyl alcohols.7 Among these propargyl
alcohols, 7−11, 13−15, and 17−23 are new. The general procedure
for the synthesis of these compounds is given below.
The PIII−Cl precursor (OCH2CMe2CH2O)PCl (24) was prepared
by a well-known method involving the reaction of the corresponding
diol with PCl3 under neat conditions.16a CH2[6-t-Bu-4-Me-
C6H2O]2PCl (25) is known,16b but in our work we have sublimed it
(150 °C/0.1 mm). Chlorodiphenylphosphine Ph2PCl (35) was
distilled prior to use.
To a mixture of the bromo or iodo compound (1.0 mmol) and
propargyl alcohol (1.2 mmol) in CH3CN (20 mL) were added
PdCl2(PPh3)2 (0.02 mmol) and CuI (0.02 mmol) under a nitrogen
atmosphere. After the reaction mixture was stirred for 5 min at room
temperature, triethylamine (4.0 equiv) was added via a syringe. The
reaction mixture was then heated to 70 °C. The solvent was removed
under reduced pressure to give the crude product, which was purified
by column chromatography on silica gel using an EtOAc−hexane
mixture as eluent.
Compound 14. This compound was prepared by using 1-iodo-2-
methoxymethoxybenzene (0.82 g, 3.1 mmol) and propargyl alcohol
(0.21 g, 3.7 mmol). It was isolated by using an ethyl acetate/hexane
(3/7) mixture as the eluent: yield 0.42 g (71%, brown oil); IR (neat,
Compound 7. This compound was prepared by using 2-(2-
bromobenzylidene)malonic acid dimethyl ester (0.96 g, 3.2 mmol)
and 2-methylbut-3-yn-2-ol (0.32 g, 3.8 mmol) and purified by column
chromatography using an ethyl acetate/hexane (3/7) mixture as the
eluent: yield 0.73 g (72%, yellow oil); IR (neat, cm−1) 3441, 2984,
1
cm−1) 3383, 2934, 1597, 1489, 1451, 1154; H NMR (400 MHz,
CDCl3) δ 2.24 (br, 1H), 3.52 (s, 3H), 4.54 (s, 2H), 5.25 (s, 2H),
6.94−6.98 (m, 1H), 7.11−7.13 (m, 1H), 7.25−7.29 (m, 1H), 7.40−
7.42 (m, 1H); 13C NMR (100 MHz, CDCl3) δ 51.8, 56.3, 81.9, 91.3,
95.0, 113.0, 115.1, 121.9, 129.9, 133.7, 157.8; LC/MS m/z 193 [M +
1]+. Anal. Calcd for C11H12O3: C, 68.74; H, 6.29. Found: C, 68.85; H,
6.38.
1
1732, 1628, 1437, 1368, 1258, 1069; H NMR (400 MHz, CDCl3) δ
1.53 and 1.65 (2 s, 6H), 2.41 (br, 1H), 3.79 and 3.86 (2 s, 6H), 7.27−
7.48 (m, 4H), 8.23 (s, 1H); 13C NMR (100 MHz, CDCl3) δ 31.3,
52.7, 52.8, 65.5, 79.3, 101.1, 124.2, 126.4, 127.4, 128.4, 130.1, 132.4,
134.7, 141.9, 164.5, 166.8; LC/MS m/z 303 [M + 1]+. Anal. Calcd for
C17H18O5: C, 67.54; H, 6.00. Found: C, 67.55; H, 6.08.
Compound 15. This compound was prepared by using 1-iodo-2-
methoxymethoxybenzene (0.73 g, 2.8 mmol) and 1-phenylprop-2-yn-
1-ol (0.44 g, 3.3 mmol). It was isolated by using an ethyl acetate/
hexane (1/4) mixture as the eluent: yield 0.48 g (65%, brown oil); IR
Compound 8. This compound was prepared by using 2-(2-
bromobenzylidene)malonic acid diethyl ester (1.26 g, 4.0 mmol) and
2-methylbut-3-yn-2-ol (0.39 g, 4.6 mmol) and purified by column
chromatography using an ethyl acetate/hexane (3/7) mixture as the
eluent: yield 0.71 g (70%, yellow oil); IR (neat, cm−1) 3434, 2980,
1
(neat, cm−1) 3400, 3065, 2928, 1597, 1489, 1447, 1154, 1001; H
NMR (400 MHz, CDCl3) δ 2.63 (br, 1H), 3.50 (s, 3H), 5.25 (s, 2H),
5.74 (s, 1H), 6.96−7.00 (m, 1H), 7.12 (d, J = 8.4 Hz, 1H), 7.27−7.47
(m, 5H), 7.68−7.70 (m, 2H); 13C NMR (100 MHz, CDCl3) δ 56.3,
65.2, 83.1, 92.8, 94.9, 113.0, 115.1, 121.8, 126.9, 128.4, 128.6, 130.0,
133.6, 140.8, 158.0; LC/MS m/z 269 [M + 1]+. Anal. Calcd for
C17H16O3: C, 76.10; H, 6.01. Found: C, 76.21; H, 5.95.
Compound 17. This compound was prepared by using 1-iodo-2-
methoxymethoxybenzene (0.80 g, 3.0 mmol) and 2-phenylbut-3-yn-2-
ol (0.53 g, 3.6 mmol). It was isolated by using an ethyl acetate/hexane
(1/4) mixture as the eluent: yield 0.58 g (68%, brown oil); IR (neat,
cm−1) 3428, 2928, 1597, 1489, 1451, 1154, 1080; 1H NMR (400
MHz, CDCl3) δ 1.91 (s, 3H), 2.70 (br, 1H), 3.53 (s, 3H), 5.27 (s,
2H), 6.99−7.03 (m, 1H), 7.13 (d, J = 8.4 Hz, 1H), 7.29−7.49 (m,
5H), 7.82−7.84 (m, 2H); 13C NMR (100 MHz, CDCl3) δ 33.3, 56.3,
70.6, 81.4, 94.9, 96.5, 113.2, 115.1, 121.8, 125.2, 127.7, 128.3, 129.8,
1
1732, 1630, 1470, 1377, 1250, 1065; H NMR (400 MHz, CDCl3) δ
1.22 and 1.34 (2 t, J = 7.6 Hz, 6H), 1.65 (s, 6H), 2.45 (br, 1H), 4.26−
4.34 (m, 4H), 7.26−7.34 (m, 2H), 7.45−7.47 (m, 2H), 8.18 (s, 1H);
13C NMR (100 MHz, CDCl3) δ 13.8, 14.2, 31.4, 61.71, 61.74, 65.6,
79.6, 100.8, 124.0, 127.4, 127.6, 128.3, 129.9, 132.4, 135.0, 140.9,
164.1, 166.4; LC/MS m/z 331 [M + 1]+. Anal. Calcd for C19H22O5: C,
69.07; H, 6.71. Found: C, 69.21; H, 6.67.
Compound 9. This compound was prepared by using 2-(2-
bromobenzylidene)malonic acid dimethyl ester (1.50 g, 5.0 mmol)
and 1-ethynyl-1-cyclohexanol (0.75 g, 6.0 mmol) and purified by
column chromatography using an ethyl acetate/hexane (3/7) mixture
as the eluent: yield 1.17 g (68%, yellow oil); IR (neat, cm−1) 3470,
2938, 1732, 1628, 1437, 1373, 1256, 1069; 1H NMR (400 MHz,
CDCl3) δ 1.27 (br, 1H), 1.61−1.78 and 2.04−2.07 (2 m, 9H), 2.50
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133.4, 145.9, 157.9; LC/MS m/z 283 [M + 1]+. Anal. Calcd for
C18H18O3: C, 76.57; H, 6.43. Found: C, 76.68; H, 6.35.
Indenes 26−34. To a solution of substituted propargyl alcohol 7
(0.60 g, 2.00 mmol) in dry THF (30 mL) was added triethylamine
(0.20 g, 0.28 mL, 2.00 mmol); the mixture was stirred for 5 min, and
then (OCH2CMe2CH2O)PCl (24; 0.34 g, 2.00 mmol) was added
dropwise at 0 °C. The contents were brought to room temperature
and then heated under reflux for 6 h. The triethylamine hydrochloride
that formed was filtered off and the solvent removed under vacuum
from the filtrate. The product 26 was purified by column
chromatography (silica gel; ethyl acetate/hexane 4/1). Compounds
27−34 were also prepared similarly.
Compound 18. This compound was prepared by using 1-iodo-2-
methoxymethoxybenzene (0.92 g, 3.5 mmol) and 1-ethynylcyclopen-
tanol (0.46 g, 4.2 mmol). It was isolated by using an ethyl acetate/
hexane (1/4) mixture as the eluent: yield 0.53 g (62%, brown oil); IR
1
(neat, cm−1) 3418, 2959, 1491, 1198, 1154, 1078; H NMR (400
MHz, CDCl3) δ 1.75−2.09 (m, 8H), 2.43 (br, 1H), 3.53 (s, 3H), 5.24
(s, 2H), 6.93−6.97 (m, 1H), 7.08 (d, J = 8.4 Hz, 1H), 7.22−7.27 (m,
1H), 7.39 (d, J = 7.2 Hz, 1H); 13C NMR (100 MHz, CDCl3) δ 23.5,
42.4, 42.5, 56.3, 75.0, 79.3, 95.1, 97.1, 113.7, 115.5, 121.9, 129.5, 133.5,
157.6, LC/MS m/z 245 [M − 1]+. Anal. Calcd for C15H18O3: C,
73.15; H, 7.37. Found: C, 73.26; H, 7.29.
Compound 26. Yield 0.70 g (81%); mp 98−100 °C (white solid);
1
IR (KBr, cm−1) 2928, 1732, 1435, 1256, 1057, 1008; H NMR (400
MHz, CDCl3) δ 0.82 and 1.01 (2 s, 6H), 2.10 (s, 3H), 3.61−3.77 (m,
8H), 4.02−4.07 (m, 2H), 4.51 (d, J = 32.8 Hz, 1H), 5.14 and 5.17 (2 s,
2H), 5.36 (s, 1H), 7.27−7.36 (m, 2H), 7.48−7.50 and 7.76−7.77 (2
m, 2H); 13C NMR (100 MHz, CDCl3) δ 21.6, 21.8, 23.7 (d, J = 6.0
Hz), 32.6 (d, J = 7.0 Hz), 50.4 (d, J = 131.0 Hz), 50.5, 52.65, 52.68,
76.0 (d, J = 7.0 Hz), 76.1 (d, J = 7.0 Hz), 117.5, 121.7, 125.2, 125.5,
127.6, 132.9 (d, J = 11.0 Hz), 137.3 (d, J = 5.0 Hz), 139.3, 143.5,
144.8, 167.9, 168.0; 31P NMR (162 MHz, CDCl3) δ 17.5; LC/MS m/z
435 [M + 1]+; HRMS (ESI) calcd for C22H28O7P [M + H]+ 435.1572,
found 435.1572. Anal. Calcd for C22H27O7P: C, 60.82; H, 6.26. Found:
C, 60.91; H, 6.21. This compound was crystallized from a
dichloromethane/hexane (3 + 1 mL) mixture. X-ray structural analysis
was done for this sample.
Compound 27. This compound was obtained by using propargyl
alcohol 8 (0.66 g, 2.0 mmol) and 24 (0.34 g, 2.0 mmol). It was
purified by column chromatography using an ethyl acetate/hexane (4/
1) mixture as the eluent: yield 0.70 g (76%, gummy material); IR
(KBr, cm−1) 2978, 1732, 1638, 1472, 1372, 1008; 1H NMR (400
MHz, CDCl3) δ 0.79 and 0.98 (2 s, 6H), 1.17−1.22 (m, 6H), 2.08 (s,
3H), 3.58−3.71 (m, 2H), 3.99−4.04 (m, 2H), 4.15−4.23 (m, 4H),
4.48 (d, J = 32.8 Hz, 1H), 5.10 and 5.16 (2 s, 2H), 5.34 (s, 1H), 7.20−
7.32 (m, 2H), 7.49−7.51 and 7.72−7.74 (2 m, 2H); 13C NMR (100
MHz, CDCl3) δ 14.0, 21.6, 21.8, 23.8, 32.6 (d, J = 7.1 Hz), 50.3 (d, J =
127.0 Hz), 61.7, 61.8, 76.0 (d, J = 6.9 Hz), 76.1 (d, J = 6.8 Hz), 117.5,
122.0, 125.1, 125.4, 127.5, 133.2 (d, J = 10.7 Hz), 137.3 (d, J = 4.9
Hz), 139.3, 143.5 (d, J = 4.8 Hz), 144.6 (d, J = 4.8 Hz), 167.5, 167.7
(d, J = 3.5 Hz); 31P NMR (162 MHz, CDCl3) δ 17.7; LC/MS m/z
463 [M + 1]+; HRMS (ESI) calcd for C24H32O7P [M + H]+ 463.1885,
found 463.1885. Anal. Calcd for C24H31O7P: C, 62.33; H, 6.76. Found:
C, 62.21; H, 6.70.
Compound 28. This compound was obtained by using propargyl
alcohol 9 (0.68 g, 2.0 mmol) and 24 (0.34 g, 2.0 mmol). It was
purified by column chromatography using an ethyl acetate/hexane (4/
1) mixture as the eluent: yield 0.72 g (76%); mp 114−116 °C (white
solid); IR (KBr, cm−1) 2936, 1728, 1441, 1256, 1063, 1009; 1H NMR
(400 MHz, CDCl3) δ 0.86 and 1.00 (2 s, 6H), 1.62−1.75 (m, 4H),
1.99−2.03 (m, 1H), 2.22 (br, 2H), 2.49−2.53 (m, 1H), 3.65−3.76 (m,
8H), 3.99−4.10 (m, 2H), 4.49 (d, J = 32.8 Hz, 1H), 5.10 (s, 1H), 5.90
(br, 1H), 7.21−7.34 (m, 2H), 7.42−7.44 and 7.74−7.76 (2 m, 2H);
13C NMR (100 MHz, CDCl3) δ 21.6, 21.9, 22.7, 25.5, 29.4, 32.6 (d, J
= 7.1 Hz), 49.8 (d, J = 131.2 Hz), 50.6, 52.8, 75.8 (d, J = 6.7 Hz), 76.0
(d, J = 6.8 Hz), 121.2, 125.2 (d, J = 3.7 Hz), 127.6, 129.6, 131.7 (d, J =
10.9 Hz), 132.8, 137.1 (d, J = 4.7 Hz), 143.8 (d, J = 5.1 Hz), 145.7 (d,
J = 6.6 Hz), 168.2, 168.3; 31P NMR (162 MHz, CDCl3) δ 18.4; LC/
MS m/z 475 [M + 1]+; HRMS (ESI) calcd for C25H32O7P [M + H]+
475.1885, found 475.1885. Anal. Calcd for C25H31O7P: C, 63.28; H,
6.59. Found: C, 63.15; H, 6.68.
Compound 19. This compound was prepared by using 1-iodo-2-
methoxymethoxybenzene (0.82 g, 6.1 mmol) and 1-ethynylcyclohex-
anol (0.91 g, 7.4 mmol). It was isolated by using an ethyl acetate/
hexane (1/4) mixture as the eluent: yield 1.10 g (69%, brown oil); IR
1
(neat, cm−1) 3397, 2932, 1597, 1574, 1449, 1155; H NMR (400
MHz, CDCl3) δ 1.26−1.74 (m, 8H), 2.01−2.03 (m, 2H), 2.65 (br,
1H), 3.51 (s, 3H), 5.24 (s, 2H), 6.93−6.97 (m, 1H), 7.07 (d, J = 8.4
Hz, 1H), 7.22−7.26 (m, 1H), 7.39 (d, J = 7.6 Hz, 1H); 13C NMR (100
MHz, CDCl3) δ 23.4, 25.3, 40.1, 56.2, 69.3, 80.7, 94.9, 97.0, 113.6,
115.2, 121.8, 129.5, 133.4, 157.7; LC/MS m/z 261 [M + 1]+. Anal.
Calcd for C16H20O3: C, 73.82; H, 7.74. Found: C, 73.69; H, 7.82.
Compound 20. This compound was prepared by using 1-iodo-2-
methoxymethoxymethylbenzene (0.89 g, 3.1 mmol) and propargyl
alcohol (0.21 g, 3.7 mmol). It was isolated by using an ethyl acetate/
hexane (1/4) mixture as the eluent: yield 0.48 g (74%, brown oil); IR
1
(neat, cm−1) 3416, 2934, 1451, 1379, 1213, 1038; H NMR (400
MHz, CDCl3) δ 2.80 (br, 1H), 3.45 (s, 3H), 4.52 (s, 2H), 4.76 and
4.78 (2 s, 4H), 7.25−7.29 (m, 1H), 7.33−7.37 (m, 1H), 7.44−7.49
(m, 2H); 13C NMR (100 MHz, CDCl3) δ 51.4, 55.4, 67.4, 83.2, 92.1,
95.7, 121.8, 127.6, 128.3, 128.7, 132.1, 139.6; LC/MS m/z 207 [M +
1]+. Anal. Calcd for C12H14O3: C, 69.88; H, 6.84. Found: C, 69.75; H,
6.91.
Compound 21. This compound was prepared by using 1-iodo-2-
methoxymethoxymethylbenzene (0.59 g, 2.1 mmol) and 2-methylbut-
3-yn-2-ol (0.21 g, 2.5 mmol). It was isolated by using an ethyl acetate/
hexane (1/4) mixture as the eluent: yield 0.38 g (76%, brown oil); IR
1
(neat, cm−1) 3414, 2982, 1601, 1377, 1150, 1049; H NMR (400
MHz, CDCl3) δ 1.62 (s, 6H), 2.89 (br, 1H), 3.44 (s, 3H), 4.746 and
4.748 (2 s, 4H), 7.23−7.27 (m, 1H), 7.31−7.35 (m, 1H), 7.41−7.47
(m, 2H); 13C NMR (100 MHz, CDCl3) δ 31.4, 55.4, 65.5, 67.1, 79.9,
95.6, 98.6, 122.0, 127.6, 128.5, 128.6, 131.9, 139.5; LC/MS m/z 235
[M + 1]+. Anal. Calcd for C14H18O3: C, 71.77; H, 7.74. Found: C,
71.62; H, 7.83.
Compound 22. This compound was prepared by using 1-iodo-2-
methoxymethoxymethylbenzene (1.69 g, 6.1 mmol) and 1-ethynylcy-
clopentanol (0.80 g, 7.3 mmol). It was isolated by using an ethyl
acetate/hexane (1/4) mixture as the eluent: yield 1.06 g (67%, brown
1
oil); IR (neat, cm−1) 3414, 2951, 1451, 1379, 1206, 1150, 1047; H
NMR (500 MHz, CDCl3) δ 1.79−1.92 and 2.03−2.10 (2 m, 8H), 2.71
(br, 1H), 3.45 (s, 3H), 4.76 and 4.77 (2 s, 4H), 7.25−7.28 (m, 1H),
7.32−7.35 (m, 1H), 7.43−7.48 (m, 2H); 13C NMR (125 MHz,
CDCl3) δ 23.5, 42.5, 55.4, 67.3, 74.8, 80.9, 95.7, 97.7, 122.2, 127.5,
128.39, 128.43, 131.9, 139.6; LC/MS m/z 261 [M + 1]+. Anal. Calcd
for C16H20O3: C, 73.82; H, 7.74. Found: C, 73.69; H, 7.79.
Compound 23. This compound was prepared by using 1-iodo-2-
methoxymethoxymethylbenzene (1.05 g, 3.8 mmol) and 1-ethynylcy-
clohexanol (0.56 g, 4.5 mmol). It was isolated by using an ethyl
acetate/hexane (1/4) mixture as the eluent: yield 1.75 g (72%, brown
Compound 29. This compound was obtained by using propargyl
alcohol 10 (0.74 g, 2.0 mmol) and 24 (0.34 g, 2.0 mmol). It was
purified by column chromatography using an ethyl acetate/hexane (4/
1) mixture as the eluent: yield 0.74 g (73%, gummy material); IR
1
oil); IR (neat, cm−1) 3412, 2934, 1601, 1449, 1150, 1049; H NMR
(400 MHz, CDCl3) δ 1.29−1.78 (m, 8H), 2.01−2.04 (m, 2H), 2.66
(br, 1H), 3.44 (s, 3H), 4.75 and 4.77 (2 s, 4H), 7.24−7.28 (m, 1H),
7.32−7.36 (m, 1H), 7.44−7.48 (m, 2H); 13C NMR (100 MHz,
CDCl3) δ 23.4, 25.3, 40.1, 55.4, 67.3, 69.1, 81.9, 95.7, 97.7, 122.1,
127.5, 128.3, 128.5, 132.1, 139.6; LC/MS m/z 275 [M + 1]+. Anal.
Calcd for C17H22O3: C, 74.42; H, 8.08. Found: C, 74.29; H, 8.12.
(iii). Reaction of Alkylidene-Based Propargylic Alcohols 7−
11 with PIII−Cl Precursors 24 and 25: Synthesis of Phosphono-
1
(neat, cm−1) 2924, 1728, 1665, 1368, 1223, 1017; H NMR (400
MHz, CDCl3) δ 0.80 and 1.01 (2 s, 6H), 1.21−1.28 (m, 6H), 1.62−
1.77 (m, 4H), 2.06−2.08 (m, 1H), 2.25−2.26 (m, 2H), 2.49−2.53 (m,
1H), 3.65−3.73 (m, 2H), 4.03−4.27 (m, 6H), 4.51 (d, J = 32.0 Hz,
1H), 5.06 (s, 1H), 5.94 (br, 1H), 7.22−7.35 (m, 2H), 7.49 and 7.77 (2
d, J = 8.0 Hz, 2H); 13C NMR (100 MHz, CDCl3) δ 14.0, 21.7, 21.9,
22.8, 25.5, 29.4, 32.6 (d, J = 7.1 Hz), 49.7 (d, J = 131.3 Hz), 51.0, 51.1,
F
dx.doi.org/10.1021/jo300705f | J. Org. Chem. XXXX, XXX, XXX−XXX

The Journal of Organic Chemistry
Article
61.7, 61.8, 75.8 (d, J = 6.9 Hz), 75.9 (d, J = 7.0 Hz), 121.5, 125.1,
127.4, 129.5 (d, J = 1.3 Hz), 132.1 (d, J = 7.0 Hz), 132.9, 137.1 (d, J =
4.8 Hz), 143.9 (d, J = 5.1 Hz), 145.5 (d, J = 6.6 Hz), 167.8 (d, J = 2.1
Hz), 168.0 (d, J = 4.1 Hz); 31P NMR (162 MHz, CDCl3) δ 18.8; LC/
MS m/z 503 [M + 1]+; HRMS (ESI) calcd for C27H36O7P [M + H]+
503.2198, found 503.2199. Anal. Calcd for C27H35O7P: C, 64.53; H,
7.02. Found: C, 64.38; H, 7.10.
solid); IR (KBr, cm−1) 2947, 1736, 1439, 1265, 1209, 1030; 1H NMR
(400 MHz, CDCl3) δ 0.79 and 1.53 (2 s, 18H), 1.57−1.63 (m, 3H),
2.06−2.29 (m, 10H), 2.60−2.64 (m, 1H), 3.38 (d, J ≈ 12.7 Hz, 1H),
3.69 and 3.71 (2 s, 6H), 4.41 (dd, J ≈ 12.7 Hz, 3.0 Hz, 1H), 4.71 (d, J
= 33.2 Hz, 1H), 5.09 (s, 1H), 5.93 (br, 1H), 6.88 and 7.00 (2 br, 2H),
7.06−7.09 (m, 2H), 7.23−7.27 (m, 1H), 7.36 (t, J ≈ 8.0 Hz, 1H), 7.58
and 7.98 (2 d, J ≈ 8.0 Hz, 2H); 13C NMR (100 MHz, CDCl3) δ 20.9,
21.0, 22.0, 22.7, 25.7, 29.6, 30.4, 31.8, 33.5, 34.3, 35.1, 50.5 (d, J =
147.1 Hz), 50.8, 52.7, 52.8, 121.8, 125.4, 126.8, 127.4, 127.7, 128.1,
128.6, 130.6, 132.2 (d, J = 10.6 Hz), 133.0, 133.6, 134.8, 136.5, 141.3
(d, J = 6.5 Hz), 141.7 (d, J = 3.7 Hz), 143.6, 144.9 (d, J = 11.0 Hz),
147.7 (d, J = 6.0 Hz), 168.1 (d, J = 4.0 Hz), 168.3 (d, J = 3.9 Hz); 31P
NMR (162 MHz, CDCl3) δ 16.4; LC/MS m/z 710 [M]+; HRMS
(ESI) calcd for C43H52O7P [M + H]+ 711.3450, found 711.3450. Anal.
Calcd for C43H51O7P: C, 72.66; H, 7.23. Found: C, 72.85; H, 7.16.
Compound 34. This compound was obtained by using propargyl
alcohol 10 (0.74 g, 2.0 mmol) and 25 (0.81 g, 2.0 mmol). It was
purified by column chromatography using an ethyl acetate/hexane (1/
4) mixture as the eluent: yield 0.99 g (67%); mp 126−128 °C (white
solid); IR (KBr, cm−1) 2924, 1732, 1603, 1454, 1155, 1032; 1H NMR
(400 MHz, CDCl3) δ 0.82 (s, 9H), 1.22−1.31 (m, 6H), 1.55 (s, 9H),
1.61 (br, 2H), 2.20, 2.24, and 2.31 (3 s, 11H), 2.63−2.67 (m, 1H),
3.40 (d, J = 12.8 Hz, 1H), 4.16−4.25 (m, 4H), 4.43 (dd, J = 12.8 Hz,
2.4 Hz, 1H), 4.73 (d, J = 32.8 Hz, 1H), 5.06 (s, 1H), 5.93 (br, 1H),
6.90 (s, 1H), 7.02−7.03 (m, 1H), 7.09−7.11 (m, 2H), 7.24−7.28 (m,
1H), 7.38 (t, J = 7.6 Hz, 1H), 7.64 and 7.98 (2 d, J = 7.6 Hz, 2H); 13C
NMR (100 MHz, CDCl3) δ 14.0, 20.9, 21.0, 22.0, 22.7, 25.7, 29.6,
30.4, 30.9, 31.7, 33.5, 34.3, 35.1, 50.4 (d, J = 146.2 Hz), 51.3, 61.6,
61.7, 122.2, 125.3, 126.6, 127.4, 127.5, 128.1, 128.6, 128.7, 130.5, 132.6
(d, J = 11.1 Hz), 133.0, 133.5 (d, J = 2.7 Hz), 133.6 (d, J = 2.9 Hz),
134.6, 134.8, 136.5, 141.3 (d, J = 4.3 Hz), 141.8 (d, J = 4.6 Hz), 143.7
(d, J = 7.0 Hz), 144.3 (d, J = 12.0 Hz), 144.9 (d, J = 12.3 Hz), 147.6
(d, J = 7.1 Hz), 167.5 (d, J = 3.8 Hz), 167.8 (d, J = 1.4 Hz); 31P NMR
(162 MHz, CDCl3) δ 16.5; LC/MS m/z 738 [M]+; HRMS (ESI)
calcd for C45H56O7P [M + H]+ 739.3763, found 739.3763. Anal. Calcd
for C45H55O7P: C, 73.15; H, 7.50. Found: C, 73.31; H, 7.42.
Compound 30. This compound was obtained by using propargyl
alcohol 11 (0.49 g, 1.6 mmol) and 24 (0.28 g, 1.6 mmol). It was
purified by column chromatography using an ethyl acetate/hexane (3/
2) mixture as the eluent: yield 0.48 g (68%); mp 144−146 °C (white
1
solid); IR (KBr, cm−1) 2980, 1696, 1580, 1470, 1381, 1277, 1057; H
NMR (400 MHz, CDCl3) δ 0.81 and 0.95 (2 s, 6H), 1.35 (t, J = 7.0
Hz, 3H), 1.64 and 1.82 (2 s, 6H), 2.33 (s, 3H), 3.35−3.42 (m, 1H),
3.84−4.05 (m, 2H), 4.16 (d, J = 32.8 Hz, 1H), 4.27−4.38 (m, 3H),
7.18−7.22 (m, 1H), 7.29−7.32 and 7.41−7.43 (2 m, 2H), 7.63−7.65
(m, 1H); 13C NMR (125 MHz, CDCl3) δ 14.3, 19.9, 21.67, 21.73, 24.5,
26.8, 32.7 (d, J = 6.3 Hz), 47.5 (d, J = 132.5 Hz), 60.2, 75.1 (d, J = 6.3
Hz), 76.4 (d, J = 7.5 Hz), 80.4, 104.0 (d, J = 2.5 Hz), 122.3, 124.7 (d, J
= 1.3 Hz), 125.1 (d, J = 2.5 Hz), 127.4, 132.4 (d, J = 7.5 Hz), 134.7 (d,
J = 11.3 Hz), 139.0 (d, J = 5.0 Hz), 142.3 (d, J = 3.8 Hz), 164.7, 166.7;
31P NMR (162 MHz, CDCl3) δ 19.3; LC/MS m/z 433 [M + 1]+;
HRMS (ESI) calcd for C23H29O6PNa [M + Na]+ 455.1600, found
455.1605. Anal. Calcd for C23H29O6P: C, 63.88; H, 6.76. Found: C,
63.72; H, 6.83.
Compound 31. This compound was obtained by using propargyl
alcohol 7 (0.60 g, 2.0 mmol) and 25 (0.81 g, 2.0 mmol). It was
purified by column chromatography using an ethyl acetate/hexane (1/
4) mixture as the eluent: yield 0.96 g (72%); mp 146−148 °C (white
solid); IR (KBr, cm−1) 2955, 1738, 1605, 1439, 1262, 1204, 1028, 922;
1H NMR (400 MHz, CDCl3) δ 0.86 and 1.53 (2 s, 18H), 2.18, 2.24,
and 2.30 (3 s, 9H), 3.36 (d, J ≈ 13.4 Hz, 1H), 3.72 and 3.73 (2 s, 6H),
4.42 (d, J ≈ 13.4 Hz, 1H), 4.74 (d, J = 32.4 Hz, 1H), 5.18 (s, 1H), 5.25
and 5.46 (2 br, 2H), 6.91 and 7.02 (2 br, 2H), 7.08−7.10 (m, 2H),
7.27−7.31 (m, 1H), 7.40 (t, J ≈ 8.0 Hz, 1H), 7.64 and 8.00 (2 d, J
∼≈8.0 Hz, 2H); 13C NMR (100 MHz, CDCl3) δ 20.9, 21.0, 23.7, 30.4,
31.8, 34.0, 34.3, 35.1, 50.7, 50.8 (d, J = 146.0 Hz), 52.7, 52.8, 119.0,
122.1, 125.7, 126.6, 127.4, 127.8, 128.1, 128.7 (d, J = 2.3 Hz), 133.0
(d, J = 11.0 Hz), 133.5 (d, J = 2.8 Hz), 134.7 (d, J = 1.3 Hz), 134.9,
136.7, 139.5, 141.2 (d, J = 4.4 Hz), 141.7 (d, J = 4.5 Hz), 143.3 (d, J =
7.1 Hz), 144.3 (d, J = 12.0 Hz), 144.8 (d, J = 12.2 Hz), 146.7 (d, J =
7.6 Hz), 167.8 (d, J = 4.2 Hz), 168.0 (d, J = 1.6 Hz); 31P NMR (162
MHz, CDCl3) δ 15.9; LC/MS m/z 672 [M + 1]+; Anal. Calcd for
C40H47O7P: C, 71.62; H, 7.06. Found: C, 71.48; H, 7.15; HRMS (ESI)
calcd for C40H48O7P [M + H]+ 671.3137, found 671.3137.
(iv). Reaction of Aldehyde-Functionalized Propargyl Alco-
hols 12 and 13 with PIII−Cl Precursors 24/35: Synthesis of
Phosphono-Indenone Derivatives 36−39. The phosphono-
indenones 36−39 were obtained by following the procedure
mentioned in section iii.
Compound 36. This compound was obtained by using propargyl
alcohol 12 (0.55 g, 2.90 mmol) and 24 (0.50 g, 2.90 mmol). It was
purified by column chromatography using an ethyl acetate/hexane (4/
1) mixture as the eluent: yield 0.71 g (75%); mp 170−172 °C (white
Compound 32. This compound was obtained by using propargyl
alcohol 8 (0.66 g, 2.0 mmol) and 25 (0.81 g, 2.0 mmol). It was
purified by column chromatography using ethyl acetate/hexane (1/4)
mixture as the eluent: yield 0.95 g (68%); mp 112−114 °C (white
1
solid); IR (KBr, cm−1) 2932, 1696, 1638, 1466, 1252, 1059, 1015; H
NMR (400 MHz, CDCl3) δ 0.75 and 0.85 (2 s, 6H), 2.17 and 2.45 (2
s, 6H), 3.51−3.63 and 4.09−4.18 (2 m, 4H), 4.56 (d, J = 23.2 Hz, 1H),
7.43−7.47 and 7.58−7.62 (m, 2H), 7.75 (d, J = 8.0 Hz, 1H), 7.82 (d, J
= 6.8 Hz, 1H); 13C NMR (100 MHz, CDCl3) δ 21.0, 21.2, 21.3, 25.8,
32.6 (d, J = 6.2 Hz), 42.8 (d, J = 136.9 Hz), 75.1, 75.3, 124.0, 127.2,
127.9, 128.5, 133.8, 139.7, 143.4, 153.0, 192.2; 31P NMR (162 MHz,
CDCl3) δ 19.8; LC/MS m/z 319 [M − 1]+; HRMS (ESI) calcd for
C17H21O4PNa [M + Na]+ 343.1075, found 343.1075. Anal. Calcd for
C17H21O4P: C, 63.74; H, 6.61. Found: C, 63.58; H, 6.71.
1
solid); IR (KBr, cm−1) 2959, 1736, 1466, 1368, 1273, 1209, 1030; H
NMR (400 MHz, CDCl3) δ 0.86 (s, 9H), 1.21−1.29 (m, 6H), 1.52 (s,
9H), 2.17, 2.23, and 2.29 (3 s, 9H), 3.35 (d, J = 13.6 Hz, 1H), 4.16−
4.24 (m, 4H), 4.41 (d, J = 13.6 Hz, 1H), 4.73 (d, J = 32.0 Hz, 1H),
5.11 (s, 1H), 5.25 and 5.45 (2 br, 2H), 6.90 and 7.01 (2 br, 2H), 7.07−
7.09 (m, 2H), 7.26−7.29 (m, 1H), 7.38 (t, J ≈ 8.0 Hz, 1H), 7.67 and
7.98 (2 d, J ≈ 8.0 Hz, 2H); 13C NMR (100 MHz, CDCl3) δ 14.0, 20.9,
21.0, 23.8, 30.4, 31.8, 34.0, 34.3, 35.1, 50.8 (d, J = 146.1 Hz), 51.2,
61.7, 61.8, 118.9, 122.5, 125.6, 126.5, 127.4, 127.6, 128.1, 128.7 (d, J =
6.9 Hz), 133.4 (d, J = 12.0 Hz), 133.5 (d, J = 2.7 Hz), 133.8 (d, J = 2.9
Hz), 134.6, 134.9, 136.7, 139.4, 141.2 (d, J = 4.3 Hz), 141.7 (d, J = 4.5
Hz), 143.3 (d, J = 6.9 Hz), 141.7 (d, J = 4.5 Hz), 143.4 (d, J = 6.9 Hz),
144.3 (d, J = 12.8 Hz), 144.8 (d, J = 12.4 Hz), 146.6 (d, J = 7.3 Hz),
167.3 (d, J = 3.9 Hz), 167.6 (d, J = 2.1 Hz); 31P NMR (162 MHz,
CDCl3) δ 15.9; LC/MS m/z 700 [M + 1]+; HRMS (ESI) calcd for
C42H51O7P [M + H]+ 699.3451, found 699.3459. Anal. Calcd for
C42H51O7P: C, 72.19; H, 7.36. Found: C, 72.05; H, 7.41.
Compound 37. This compound was prepared by using propargyl
alcohol 13 (0.74 g, 3.3 mmol) and 24 (0.55 g, 3.3 mmol): yield 0.82 g
(70%); mp 162−164 °C (white solid); IR (KBr, cm−1) 2930, 1711,
1
1599, 1462, 1235, 1053, 1001; H NMR (400 MHz, CDCl3) δ 0.82
and 0.86 (2 s, 6H), 1.66−1.91 (m, 6H), 2.46−2.58 and 3.07−3.32 (m,
4H), 3.55−3.62 and 4.10−4.21 (2 m, 4H), 4.61 (d, J = 23.2 Hz, 1H),
7.44−7.48 and 7.59−7.63 (m, 2H), 7.75−7.77 (m, 1H), 7.83 (d, J =
7.6 Hz, 1H); 13C NMR (100 MHz, CDCl3) δ 21.3, 21.5, 26.2, 27.9,
28.1, 29.2 (d, J = 1.8 Hz), 32.6 (d, J = 6.0 Hz), 35.2 (d, J = 1.3 Hz),
42.3 (d, J = 136.8 Hz), 75.1 (d, J = 6.5 Hz), 75.2 (d, J = 6.6 Hz), 124.0
(d, J = 2.4 Hz), 125.2 (d, J = 7.3 Hz), 127.1 (d, J = 4.0 Hz), 128.4 (d, J
= 2.9 Hz), 133.8 (d, J = 3.1 Hz), 140.0 (d, J = 5.8 Hz), 143.2 (d, J =
9.5 Hz), 160.2 (d, J = 5.9 Hz), 192.6; 31P NMR (162 MHz, CDCl3) δ
19.9; LC/MS m/z 361 [M + 1]+; HRMS (ESI) calcd for
Compound 33. This compound was obtained by using propargyl
alcohol 9 (0.68 g, 2.0 mmol) and 25 (0.81 g, 2.0 mmol). It was
purified by column chromatography using an ethyl acetate/hexane (1/
4) mixture as the eluent: yield 0.99 g (70%); mp 184−186 °C (white
G
dx.doi.org/10.1021/jo300705f | J. Org. Chem. XXXX, XXX, XXX−XXX

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C20H25O4PNa [M + Na]+ 383.1388, found 383.1388. Anal. Calcd for
C20H25O4P: C, 66.66; H, 6.99. Found: C, 66.82; H, 6.91.
128.0, 128.6 (d, J = 4.1 Hz), 128.7, 128.9, 130.9 (d, J = 3.7 Hz), 131.2
(d, J = 2.6 Hz), 131.5, 131.6, 131.8, 133.8 (d, J = 105.1 Hz), 154.7 (d, J
= 4.3 Hz), 211.4 (d, J = 6.3 Hz); 31P NMR (162 MHz, CDCl3) δ 30.6;
LC/MS m/z 405 [M + 1]+. Anal. Calcd for C25H25O3P: C, 74.24; H,
6.23. Found: C, 74.12; H, 6.35.
Compound 38. This compound was prepared by using propargyl
alcohol 12 (0.55 g, 2.9 mmol) and 35 (0.64 g, 2.9 mmol): yield 0.84 g
(78%); mp 212−214 °C (white solid); IR (KBr, cm−1) 2934, 1684,
1620, 1435, 1292, 1194, 1111; 1H NMR (400 MHz, CDCl3) δ 1.85 (s,
3H), 2.35 (d, J = 2.8 Hz, 3H), 5.01 (d, J = 17.2 Hz, 1H), 7.01 (d, J =
7.2 Hz, 1H), 7.28−7.51 (m, 10H), 7.59 (d, J = 7.2 Hz, 1H), 7.69−7.74
(m, 2H); 13C NMR (100 MHz, CDCl3) δ 21.0, 25.8, 47.7 (d, J = 62.7
Hz), 123.9 (d, J = 15.5 Hz), 127.8, 128.1, 128.2, 128.6, 130.8, 131.5,
131.7, 132.2, 132.3, 133.4, 140.1, 143.9, 153.6, 192.0; 31P NMR (162
MHz, CDCl3) δ 32.0; LC/MS m/z 373 [M + 1]+; HRMS (ESI) calcd
for C24H21O2PNa [M + Na]+ 395.1177, found 395.1177. Anal. Calcd
for C24H21O2P: C, 77.41; H, 5.68. Found: C, 77.35; H, 5.61. This
compound was crystallized from tetrahydrofuran (2 mL) at 30 °C. An
X-ray structure was determined for this sample.
Compound 43. This compound was prepared from propargyl
alcohol 17 (0.76 g, 2.7 mmol) and 35 (0.59 g, 2.7 mmol). It was
isolated by using an ethyl acetate/hexane (3/2) mixture as the eluent:
yield 1.06 g (85%, gummy material); IR (neat, cm−1) 2955, 1931,
1730, 1595, 1491, 1439; 1H NMR (500 MHz, CDCl3) δ 1.87 (s, 3H),
3.27 (s, 3H), 4.93 (s, 2H), 6.94−6.97 (m, 1H), 7.10−7.46 (m, 13H),
7.71−7.80 (m, 5H); 13C NMR (125 MHz, CDCl3) δ 15.7 (d, J = 5.9
Hz), 55.8, 94.4, 98.4 (d, J = 100.9 Hz), 102.7 (d, J = 14.1 Hz), 114.3,
121.9, 125.9 (d, J = 1.5 Hz), 127.2, 127.9, 128.0, 128.1, 128.2, 129.1,
130.80, 130.82, 131.4, 131.49, 131.52, 131.57, 131.60, 132.6, 132.8, 133.0
(d, J = 105.8 Hz), 133.7, 134.9 (d, J = 6.6 Hz), 154.8 (d, J = 4.9 Hz),
213.8 (d, J = 5.5 Hz); 31P NMR (162 MHz, CDCl3) δ 30.4; LC/MS
m/z 467 [M + 1]+. Anal. Calcd for C30H27O3P: C, 77.24; H, 5.83.
Found: C, 77.45; H, 5.76.
Compound 39. This compound was prepared by using propargyl
alcohol 13 (0.74 g, 3.3 mmol) and 35 (0.73 g, 3.3 mmol): yield 0.97 g
(71%); mp 174−176 °C (white solid); IR (KBr, cm−1) 2928, 1705,
1
1603, 1439, 1186, 1119; H NMR (400 MHz, CDCl3) δ 1.56−2.35
Compound 44. This compound was prepared from propargyl
alcohol 18 (0.62 g, 2.5 mmol) and 35 (0.56 g, 2.5 mmol). It was
isolated by using an ethyl acetate/hexane (3/2) mixture as the eluent:
yield 0.89 g (82%, gummy material); IR (neat, cm−1) 2955, 1946,
(m, 8H), 2.82−2.85 and 3.33−3.35 (m, 2H), 5.06 (d, J = 17.2 Hz,
1H), 6.95−6.97 (m, 1H), 7.27−7.60 (m, 11H), 7.71−7.75 (m, 2H);
13C NMR (125 MHz, CDCl3) δ 26.2, 28.2, 28.3, 29.3, 35.3, 47.1 (d, J
1
1593, 1489, 1437, 1236, 1117; H NMR (400 MHz, CDCl3) δ 1.32−
= 62.5 Hz), 123.9 (d, J = 2.4 Hz), 125.8 (d, J = 4.5 Hz), 126.5 (d, J =
3.4 Hz), 128.0, 128.1, 128.4, 128.5, 131.5, 131.6, 132.0 (d, J = 3.3 Hz),
132.1 (d, J = 2.6 Hz), 132.4, 132.5, 133.2 (d, J = 2.6 Hz), 140.5 (d, J =
4.6 Hz), 143.8 (d, J = 5.1 Hz), 161.2 (d, J = 4.9 Hz), 192.4; 31P NMR
(162 MHz, CDCl3) δ 32.2; LC/MS m/z 411 [M − 1]+; HRMS (ESI)
calcd for C27H26O2P [M + H]+ 413.1670, found 413.1670. Anal. Calcd
for C27H25O2P: C, 78.62; H, 6.11. Found: C, 78.51; H, 6.02.
(v). Synthesis of Functionalized Allenes 40−55. (a). Synthesis
of Allenes 40−45. The phosphorus-based allenes 40−45 were
synthesized according to literature procedures.6
Compound 40. This compound was prepared from propargyl
alcohol 14 (0.92 g, 4.8 mmol) and 35 (1.06 g, 4.8 mmol). It was
isolated by using an ethyl acetate/hexane (3/2) mixture as the eluent:
yield 1.42 g (79%, gummy material); IR (neat, cm−1) 2982, 1925,
1597, 1491, 1364, 1155; 1H NMR (400 MHz, CDCl3) δ 3.33 (s, 3H),
4.79 and 4.82 (2 s, 2H), 4.92 (s, 2H), 6.91−6.95 (m, 1H), 7.06 (d, J =
8.0 Hz, 1H), 7.16−7.20 (m, 1H), 7.39−7.49 (m, 7H), 7.75−7.80 (m,
4H); 13C NMR (100 MHz, CDCl3) δ 56.0, 76.5 (d, J = 12.5 Hz), 94.5,
96.7 (d, J = 101.2 Hz), 114.5, 121.7 (d, J = 4.8 Hz), 121.9, 128.0,
128.1, 129.4, 130.8 (d, J = 3.7 Hz), 131.5 (d, J = 2.8 Hz), 131.7, 131.8,
133.0 (d, J = 106.4 Hz), 154.7 (d, J = 3.9 Hz), 214.1 (d, J = 6.7 Hz);
31P NMR (162 MHz, CDCl3) δ 27.9; LC/MS m/z 377 [M + 1]+.
1.34 (m, 2H), 1.50−1.51 (m, 2H), 1.90−1.95 (m, 2H), 2.33−2.38 (m,
2H), 3.30 (s, 3H), 4.93 (s, 2H), 6.90−6.93 (m, 1H), 7.05 (d, J = 8.0
Hz, 1H), 7.13−7.17 (m, 1H), 7.40−7.56 (m, 7H), 7.74−7.78 (m, 4H);
13C NMR (100 MHz, CDCl3) δ 26.9, 30.59, 30.64, 55.9, 94.6, 96.8 (d, J
= 105.1 Hz), 105.7 (d, J = 14.5 Hz), 114.4, 121.8, 123.3 (d, J = 6.9
Hz), 127.9, 128.0, 128.6, 128.8, 130.9, 131.1, 131.5, 131.6, 131.8,
132.5, 134.1 (d, J = 105.3 Hz), 154.6 (d, J = 4.1 Hz), 207.1 (d, J = 5.9
Hz); 31P NMR (162 MHz, CDCl3) δ 31.1; LC/MS m/z 432 [M + 1]+.
Anal. Calcd for C27H27O3P: C, 75.33; H, 6.32. Found: C, 75.51; H,
6.18.
Compound 45. This compound was prepared from propargyl
alcohol 19 (0.79 g, 3.0 mmol) and 35 (0.67 g, 3.0 mmol). It was
isolated by using an ethyl acetate/hexane (3/2) mixture as the eluent:
yield 1.10 g (82%, gummy material); IR (neat, cm−1) 2930, 1950,
1
1738, 1591, 1439, 1117; H NMR (400 MHz, CDCl3) δ 0.98−1.07
(m, 2H), 1.30−1.51 (m, 4H), 1.89−2.06 (m, 4H), 3.34 (s, 3H), 4.96
(s, 2H), 6.92−6.96 (m, 1H), 7.08−7.24 (m, 3H), 7.41−7.81 (m,
10H); 13C NMR (100 MHz, CDCl3) δ 25.4, 26.0, 26.1, 29.6, 29.7,
55.8, 94.52, 94.54 (d, J = 106.3 Hz), 103.4 (d, J = 13.8 Hz), 114.4,
121.8, 123.3 (d, J = 7.1 Hz), 128.0, 128.1, 128.8, 130.9 (d, J = 3.6 Hz),
131.1, 131.2 (d, J = 2.6 Hz), 131.4, 131.6, 131.7, 133.9 (d, J = 105.3
Hz), 154.7 (d, J = 4.0 Hz), 208.1 (d, J = 7.2 Hz); 31P NMR (162 MHz,
CDCl3) δ 30.8; LC/MS m/z 445 [M + 1]+. Anal. Calcd for
C28H29O3P: C, 75.66; H, 6.58. Found: C, 75.48; H, 6.63.
Anal. Calcd for C23H21O3P: C, 73.39; H, 5.62. Found: C, 73.29; H,
5.68.
Compound 41. This compound was prepared from propargyl
alcohol 15 (0.57 g, 2.2 mmol) and 35 (0.47 g, 2.2 mmol). It was
isolated by using an ethyl acetate/hexane (3/2) mixture as the eluent:
yield 0.77 g (80%, gummy material); IR (neat, cm−1) 3057, 1933,
(b). Synthesis of Phenol-Based Allenes 46−51. To a homogeneous
solution of allene 40 (0.20 g, 0.50 mmol) in ethyl acetate (2 mL) was
added hydrochloric acid (35%, 1.0 mL), and the contents were stirred
for 5 min. To this stirred solution was added water (10 mL) after
completion of the reaction (TLC or 31P NMR). The organic layer was
separated, and the aqueous layer was washed with EtOAc (10 mL).
The combined organic layer was washed with brine solution and dried
(Na2SO4), the solvent removed by a rotary evaporator, and the
product 46 thus obtained was used as such for the next step.
Compounds 47−51 were also prepared similarly.
1
1595, 1489, 1439, 1242, 1194, 1117; H NMR (400 MHz, CDCl3) δ
3.23 (s, 3H), 4.93 (s, 2H), 6.17 (d, J = 10.8 Hz, 1H), 6.91−6.95 (m,
1H), 7.09−7.43 (m, 13H), 7.66−7.85 (m, 5H); 13C NMR (100 MHz,
CDCl3) δ 55.9, 94.3, 96.0 (d, J = 13.5 Hz), 100.5 (d, J = 99.7 Hz),
114.2, 121.7 (d, J = 5.4 Hz), 121.9, 127.2 (d, J = 2.0 Hz), 127.5, 128.0
(d, J = 1.2 Hz), 128.1 (d, J = 1.2 Hz), 128.5, 129.4, 130.6 (d, J = 3.4
Hz), 131.5, 131.61, 131.64, 131.7, 132.7 (d, J = 106.1 Hz), 132.8 (d, J =
105.2 Hz), 154.7 (d, J = 4.6 Hz), 213.8 (d, J = 5.5 Hz); 31P NMR (162
MHz, CDCl3) δ 28.9; LC-MS m/z 452 [M]+. Anal. Calcd for
C29H25O3P: C, 76.98; H, 5.57. Found: C, 76.85; H, 5.67.
Compound 46. Yield 0.16 g (90%); mp 124−126 °C (white solid);
1
IR (KBr, cm−1) 3059, 1925, 1715, 1485, 1437, 1246, 1154, 1121; H
NMR (400 MHz, CDCl3) δ 4.80 and 4.82 (2 s, 2H), 6.78−6.81 (m,
1H), 6.94 (d, J = 8.0 Hz, 1H), 7.12−7.17 (m, 2H), 7.47−7.57 (m,
6H), 7.74−7.79 (m, 4H), 10.67 (s, 1H); 13C NMR (100 MHz,
CDCl3) δ 76.4 (d, J = 12.1 Hz), 99.5 (d, J = 99.5 Hz), 119.4, 120.1,
128.5, 128.6, 129.3, 130.3, 131.9, 132.0, 132.6, 155.7, 214.3 (d, J = 8.5
Hz); 31P NMR (162 MHz, CDCl3) δ 36.0; LC/MS m/z 333 [M + 1]+.
Anal. Calcd for C21H17O2P: C, 75.90; H, 5.16. Found: C, 75.81; H,
5.23. This compound was crystallized from an ethyl acetate/hexane
(9/1) mixture at 25 °C. An X-ray structure was determined for this
sample.
Compound 42. This compound was prepared from propargyl
alcohol 16 (0.48 g, 2.2 mmol) and 35 (0.48 g, 2.2 mmol). It was
isolated by using an ethyl acetate/hexane (3/2) mixture as the eluent:
yield 0.74 g (84%, gummy material); IR (neat, cm−1) 2907, 1954,
1
1738, 1593, 1489, 1439, 1366, 1236; H NMR (400 MHz, CDCl3) δ
1.45 and 1.47 (2 s, 6H), 3.32 (s, 3H), 4.95 (s, 2H), 6.90−6.94 (m,
1H), 7.05−7.18 (m, 2H), 7.40−7.55 (m, 8H), 7.74−7.81 (m, 3H); 13C
NMR (100 MHz, CDCl3) δ 18.8, 18.9, 55.8, 94.5, 94.6 (d, J = 104.5
Hz), 97.4 (d, J = 13.8 Hz), 114.4, 121.8, 123.0 (d, J = 7.0 Hz), 127.9,
H
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Compound 47. This product was synthesized from compound 41
(0.20 g, 0.4 mmol): yield 0.16 g (91%); mp 134−136 °C (white solid);
31P NMR (162 MHz, CDCl3) δ 30.3; LC/MS m/z 391 [M + 1]+.
Anal. Calcd for C24H23O3P: C, 73.83; H, 5.94. Found: C, 73.91; H,
5.85.
1
IR (KBr, cm−1) 3061, 1931, 1736, 1439, 1244, 1161, 1119; H NMR
(500 MHz, CDCl3) δ 6.23 (d, J = 10.8 Hz, 1H), 6.77−6.81 (m, 1H),
6.96−7.52 (m, 14H), 7.74−7.81 (m, 4H), 10.80 (s, 1H); 13C NMR
(125 MHz, CDCl3) δ 96.5 (d, J = 12.8 Hz), 104.3 (d, J = 97.5 Hz),
119.4, 119.7 (d, J = 4.8 Hz), 120.2, 127.0 (d, J = 1.6 Hz), 128.1, 128.4,
128.5, 128.6, 128.8, 130.5, 131.67, 131.72, 131.75, 131.9, 132.5 (d, J =
2.6 Hz), 132.6 (d, J = 2.6 Hz), 155.7, 213.8 (d, J = 7.1 Hz); 31P NMR
(162 MHz, CDCl3) δ 36.2; LC/MS m/z 407 [M − 1]+. Anal. Calcd
for C27H21O2P: C, 79.40; H, 5.18. Found: C, 79.26; H, 5.22.
Compound 53. This compound was prepared from propargyl
alcohol 21 (0.44 g, 1.9 mmol) and 35 (0.42 g, 1.9 mmol). It was
isolated by using an ethyl acetate/hexane (3/2) mixture as the eluent:
yield 0.64 g (81%, gummy material); IR (neat, cm−1) 2924, 1948,
1439, 1186, 1117, 1042; 1H NMR (400 MHz, CDCl3) δ 1.48 and 1.49
(2 s, 6H), 3.39 (s, 3H), 4.67 and 4.71 (2 s, 4H), 7.12−7.23 (m, 2H),
7.40−7.53 (m, 8H), 7.73−7.79 (m, 4H); 13C NMR (100 MHz,
CDCl3) δ 18.86, 18.90, 55.3, 66.7, 95.7, 96.8 (d, J = 100.1 Hz), 97.8 (d,
J = 13.6 Hz), 127.3, 127.6, 128.1, 128.18, 128.20, 129.8 (d, J = 2.6 Hz),
131.6 (d, J = 2.3 Hz), 131.68, 131.72, 132.7 (d, J = 103.9 Hz), 136.6 (d,
J = 5.5 Hz), 209.8 (d, J = 6.0 Hz); 31P NMR (162 MHz, CDCl3) δ
30.3; LC/MS m/z 419 [M + 1]+. Anal. Calcd for C26H27O3P: C,
74.62; H, 6.50. Found: C, 74.53; H, 6.58.
Compound 48. This product was synthesized from compound 42
(0.20 g, 0.5 mmol): yield 0.17 g (96%); mp 142−144 °C (white solid);
1
IR (KBr, cm−1) 3057, 2924, 1956, 1524, 1437, 1254, 1148; H NMR
NMR (400 MHz, CDCl3) δ 1.47 and 1.48 (2 s, 6H), 6.76−6.80 (m,
1H), 6.92 (d, J = 7.6 Hz, 1H), 7.09−7.15 (m, 2H), 7.44−7.55 (m,
6H), 7.72−7.76 (m, 4H), 10.80 (s, 1H); 13C NMR (100 MHz,
CDCl3) δ 19.08, 19.13, 97.9 (d, J = 100.9 Hz), 98.3 (d, J = 13.4 Hz),
119.2, 119.9, 120.9 (d, J = 6.0 Hz), 128.4, 128.5, 129.9, 130.7 (d, J =
106.2 Hz), 131.7, 131.8, 132.3, 155.7, 211.8 (d, J = 7.2 Hz); 31P NMR
(162 MHz, CDCl3) δ 37.9; LC/MS m/z 361 [M + 1]+. Anal. Calcd for
C23H21O2P: C, 76.65; H, 5.87. Found: C, 76.75; H, 5.82.
Compound 54. This compound was prepared from propargyl
alcohol 22 (1.23 g, 4.7 mmol) and 35 (1.04 g, 4.7 mmol). It was
isolated by using an ethyl acetate/hexane (3/2) mixture as the eluent:
yield 1.51 g (72%, gummy material); IR (neat, cm−1) 2953, 1942,
1
1437, 1379, 1283, 1188, 1044; H NMR (400 MHz, CDCl3) δ 1.30−
1.32 (m, 2H), 1.48−1.50 (m, 2H), 1.94−1.99 (m, 2H), 2.32−2.37 (m,
2H), 3.39 (s, 3H), 4.68 and 4.70 (2 s, 4H), 7.11−7.22 (m, 2H), 7.38−
7.60 (m, 8H), 7.73−7.78 (m, 4H); 13C NMR (100 MHz, CDCl3) δ
26.9, 30.57, 30.62, 55.3, 66.8, 95.8, 98.4 (d, J = 100.8 Hz), 106.1 (d, J =
14.1 Hz), 127.3, 127.6, 128.0, 128.1, 128.2, 129.5, 131.56, 131.63,
131.7, 132.9 (d, J = 104.1 Hz), 136.5 (d, J = 5.5 Hz), 205.9 (d, J = 5.6
Hz); 31P NMR (162 MHz, CDCl3) δ 31.1; LC/MS m/z 445 [M + 1]+.
Anal. Calcd for C28H29O3P: C, 75.66; H, 6.58. Found: C, 75.48; H,
6.64.
Compound 49. This product was synthesized from compound 43
(0.28 g, 0.6 mmol): yield 0.23 g (92%); mp 170−172 °C (white solid);
1
IR (KBr, cm−1) 3059, 1931, 1738, 1439, 1244, 1159, 1121; H NMR
(400 MHz, CDCl3) δ 1.88 (d, J = 5.6 Hz, 3H), 6.79−6.82 (m, 1H),
6.97 (d, J = 8.0 Hz, 1H), 7.16−7.53 (m, 13H), 7.71−7.77 (m, 4H),
10.81 (s, 1H); 13C NMR (100 MHz, CDCl3) δ 16.2 (d, J = 5.5 Hz),
102.0 (d, J = 98.6 Hz), 103.7 (d, J = 13.2 Hz), 116.1, 119.4, 120.1,
125.7, 127.8, 128.3, 128.4, 128.5, 130.2 (d, J = 106.7 Hz), 130.3, 131.6,
131.7, 131.8, 132.4, 134.2 (d, J = 6.2 Hz), 155.7, 214.0 (d, J = 6.3 Hz);
31P NMR (162 MHz, CDCl3) δ 37.1; LC/MS m/z 423 [M + 1]+.
Anal. Calcd for C28H23O2P: C, 79.61; H, 5.49. Found: C, 79.55; H,
5.52.
Compound 55. This compound was prepared from propargyl
alcohol 23 (2.11 g, 7.7 mmol) and 35 (1.70 g, 7.7 mmol). It was
isolated by using an ethyl acetate/hexane (3/2) mixture as the eluent:
yield 2.65 g (75%, gummy material); IR (neat, cm−1) 2932, 1944,
1
Compound 50. This product was synthesized from compound 44
1591, 1437, 1190, 1117, 1044; H NMR (400 MHz, CDCl3) δ 1.01−
(0.20 g, 0.5 mmol): yield 0.16 g (90%); mp 148−150 °C (white solid);
1.04 (m, 2H), 1.30−1.48 (m, 4H), 1.92−2.04 (m, 4H), 3.41 (s, 3H),
4.69 and 4.74 (2 s, 4H), 7.13−7.25 (m, 2H), 7.41−7.57 (m, 8H),
7.75−7.80 (m, 4H); 13C NMR (100 MHz, CDCl3) δ 25.3, 25.9, 26.0,
29.6, 29.7, 55.3, 66.6, 95.7, 96.6 (d, J = 100.3 Hz), 103.7 (d, J = 13.9
Hz), 127.3, 127.5, 127.9, 128.2, 128.3, 129.8 (d, J = 2.9 Hz), 131.5 (d, J
= 3.0 Hz), 131.77, 131.84, 132.0, 132.9 (d, J = 102.9 Hz), 136.6 (d, J =
6.4 Hz), 206.5 (d, J = 6.8 Hz); 31P NMR (162 MHz, CDCl3) δ 30.2;
LC/MS m/z 457 [M − 1]+. Anal. Calcd for C29H31O3P: C, 75.96; H,
6.81. Found: C, 75.85; H, 6.72.
1
IR (KBr, cm−1) 3057, 1944, 1595, 1453, 1281, 1152, 1096; H NMR
NMR (400 MHz, CDCl3) δ 1.28 (br, 2H), 1.54 (br, 2H), 1.95 (br,
2H), 2.41−2.42 (m, 2H), 6.77−6.80 (m, 1H), 6.91−6.95 (m, 1H),
7.13 (br, 2H), 7.46−7.53 (m, 6H), 7.72−7.76 (m, 4H), 10.76 (s, 1H);
13C NMR (125 MHz, CDCl3) δ 26.9, 31.0 (d, J = 4.4 Hz), 100.1 (d, J
= 102.5 Hz), 106.3 (d, J = 13.8 Hz), 119.2, 119.9, 121.2, 128.3, 128.4,
129.9, 131.0 (d, J = 106.0 Hz), 131.7, 131.8, 132.2, 155.7, 207.3 (d, J =
8.5 Hz); 31P NMR (162 MHz, CDCl3) δ 38.3; LC/MS m/z 387 [M +
1]+. Anal. Calcd for C25H23O2P: C, 77.70; H, 6.00. Found: C, 77.56;
H, 6.12.
Compound 51. This product was synthesized from compound 45
(0.20 g, 0.4 mmol): yield 0.15 g (94%); mp 162−164 °C (white solid);
IR (KBr, cm−1) 3057, 2928, 1941, 1572, 1483, 1439, 1404, 1294, 1244,
1148; 1H NMR (400 MHz, CDCl3) δ 0.97−1.48 (m, 6H), 1.81−2.06
(m, 4H), 6.77−6.81 (m, 1H), 6.93 (d, J = 8.0 Hz, 1H), 7.09−7.16 (m,
2H), 7.48−7.55 (m, 6H), 7.74−7.89 (m, 4H), 10.84 (s, 1H); 13C
NMR (100 MHz, CDCl3) δ 25.2, 26.1, 29.87, 29.91, 97.8 (d, J = 105.9
Hz), 104.0 (d, J = 13.1 Hz), 119.1, 119.9, 121.3 (d, J = 7.8 Hz), 128.4,
128.6, 129.8, 130.8 (d, J = 106.7 Hz), 131.8, 131.9, 132.2, 155.7, 208.4
(d, J = 9.1 Hz); 31P NMR (162 MHz, CDCl3) δ 37.6; LC/MS m/z
401 [M + 1]+. Anal. Calcd for C26H25O2P: C, 77.98; H, 6.29. Found:
C, 77.81; H, 6.37.
(c). Synthesis of Allenes 52−55. The phosphorus-based allenes
52−55 were synthesized according to literature procedures.6
Compound 52. This compound was prepared from propargyl
alcohol 20 (0.44 g, 2.1 mmol) and 35 (0.47 g, 2.1 mmol). It was
isolated by using an ethyl acetate/hexane (3/2) mixture as the eluent:
yield 0.66 g (79%, gummy material); IR (neat, cm−1) 3059, 1933,
1591, 1439, 1262, 1044; 1H NMR (400 MHz, CDCl3) δ 3.39 (s, 3H),
4.64 and 4.66 (2 s, 4H), 4.85 and 4.87 (2 s, 2H), 7.13−7.27 (m, 2H),
7.35−7.53 (m, 8H), 7.76−7.81 (m, 4H); 13C NMR (100 MHz,
CDCl3) δ 55.4, 66.7, 95.8, 98.3 (d, J = 97.6 Hz), 127.6, 128.1, 128.2,
128.3, 128.7, 129.7 (d, J = 2.9 Hz), 130.5 (d, J = 4.9 Hz), 131.6 (d, J =
105.2 Hz), 131.9, 132.0, 136.9 (d, J = 4.9 Hz), 212.2 (d, J = 6.6 Hz);
(vi). Cyclization Reactions of Allenes 46−51 Possessing a 2-
Hydroxyphenol Side Group: Synthesis of 1,2-Disubstituted
Benzofuran Derivatives 56−61. To a solution of allene 46 (0.10 g,
0.30 mmol) in THF (2 mL) was added triethylamine (0.04 mL, 0.30
mmol), and the mixture was stirred at 70 °C for 1 h. The solvent was
removed by rotary evaporation, and the crude product thus obtained
was purified by column chromatography (silica gel; 4/1 ethyl acetate/
hexane) to yield the colorless solid product 56. Compounds 57−61
were also prepared by following the same method.
Compound 56. This compound is known but was prepared by an
entirely different (multistep) route:11 yield 0.10 g (95%); mp 142−144
°C (white solid); IR (KBr, cm−1) 2851, 1925, 1485, 1437, 1246, 1154,
1119; the 1H NMR spectrum was identical with that reported
before;11 13C NMR (100 MHz, CDCl3) δ 14.5, 105.9 (d, J = 119.0
Hz), 110.9, 120.8, 123.3, 124.1, 128.7, 128.8, 131.7, 131.8, 132.2 (d, J
= 3.0 Hz), 133.1 (d, J = 109.0 Hz), 154.1 (d, J = 11.0 Hz), 164.7 (d, J
= 18.0 Hz); 31P NMR (162 MHz, CDCl3) δ 21.3; LC/MS m/z 333
[M + 1]+. Anal. Calcd for C21H17O2P: C, 75.90; H, 5.16. Found: C,
75.86; H, 5.09.
Compound 57. This product was synthesized from the allene 47
(0.10 g, 0.2 mmol). It was isolated by using an ethyl acetate/hexane
(7/3) mixture as the eluent: yield 0.09 g (89%); mp 140−142 °C
(white solid); IR (KBr, cm−1) 3057, 1555, 1453, 1435, 1306, 1254,
1190, 1121; 1H NMR (400 MHz, CDCl3) δ 4.49 (s, 2H), 6.69 (d, J =
7.2 Hz, 1H), 6.99−7.03 (m, 1H), 7.18−7.31 (m, 6H), 7.44−7.58 (m,
7H), 7.73−7.79 (m, 4H); 13C NMR (100 MHz, CDCl3) δ 34.2, 106.4
I
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(d, J = 117.9 Hz), 111.3, 121.1, 123.4, 124.4, 126.6, 128.5, 128.7,
128.8, 129.2, 131.7, 131.8, 132.3, 133.2 (d, J = 108.4 Hz), 137.0, 154.5
(d, J = 11.5 Hz), 166.3 (d, J = 17.8 Hz); 31P NMR (162 MHz, CDCl3)
δ 21.5; LC/MS m/z 409 [M + 1]+; HRMS (ESI) calcd for
C27H21O2PNa [M + Na]+ 431.1177, found 431.1177. Anal. Calcd
for C27H21O2P: C, 79.40; H, 5.18. Found: C, 79.55; H, 5.12.
Compound 58. This product was synthesized from the allene 48
(0.10 g, 0.3 mmol). It was isolated by using an ethyl acetate/hexane
(7:3) mixture as the eluent: yield 0.09 g (90%); mp 128−130 °C
(white solid); IR (KBr, cm−1) 2868, 1559, 1437, 1250, 1194, 1119; 1H
NMR (400 MHz, CDCl3) δ 1.27 (d, J = 6.8 Hz, 6H), 3.65−3.72 (m,
1H), 6.61 (d, J = 7.6 Hz, 1H), 6.97−7.01 (m, 1H), 7.20−7.23 (m,
1H), 7.47−7.59 (m, 7H), 7.72−7.76 (m, 4H); 13C NMR (100 MHz,
CDCl3) δ 21.1, 27.8, 103.9 (d, J = 119.6 Hz), 111.1, 121.0, 123.2,
124.0, 128.6, 128.7, 131.7, 131.8, 132.1 (d, J = 2.6 Hz), 133.4 (d, J =
108.3 Hz), 154.1 (d, J = 11.7 Hz), 172.7 (d, J = 18.8 Hz); 31P NMR
(162 MHz, CDCl3) δ 21.5; LC/MS m/z 361 [M + 1]+; HRMS (ESI)
calcd for C23H22O2P [M + H]+ 361.1357, found 361.1357. Anal. Calcd
for C23H21O2P: C, 76.65; H, 5.87. Found: C, 76.52; H, 5.93.
EtOAc. The combined organic layer was washed with saturated
aqueous NaCl. After drying over Na2SO4, the solvent was removed in
vacuo. The product 62 was purified by column chromatography (silica
gel; ethyl acetate/hexane 4/1). Compounds 63−65 were also prepared
similarly.
Compound 62. Yield 0.24 g (90%, gummy solid); IR (neat, cm−1)
2926, 1588, 1561, 1487, 1437, 1265, 1159, 1049; 1H NMR (400 MHz,
CDCl3) δ 1.90 (d, J = 1.2 Hz, 3H), 5.08 (s, 2H), 6.96−6.97 (m, 2H),
7.07−7.09 (m, 2H), 7.41−7.52 (m, 6H), 7.78−7.83 (m, 4H); 13C
NMR (100 MHz, CDCl3) δ 21.0, 69.3, 104.9 (d, J = 113.9 Hz), 123.9,
124.4 (d, J = 3.5 Hz), 125.9, 127.0 (d, J = 7.3 Hz), 127.9, 128.6, 128.8,
130.7 (d, J = 7.6 Hz), 131.5, 131.6, 134.6 (d, J = 105.7 Hz), 168.8 (d, J
= 17.2 Hz); 31P NMR (162 MHz, CDCl3) δ 26.5; LC/MS m/z 347
[M + 1]+; HRMS (ESI) calcd for C22H20O2P [M + H]+ 347.1201,
found 347.1201. Anal. Calcd for C22H19O2P: C, 76.29; H, 5.53. Found:
C, 76.41; H, 5.58.
Compound 63. This product was synthesized from the allene 53
(0.25 g, 0.6 mmol): yield 0.21 g (92%); mp 162−164 °C (white solid);
1
IR (KBr, cm−1) 2971, 1588, 1483, 1437, 1223, 1161, 1117; H NMR
(400 MHz, CDCl3) δ 0.91 (d, J = 6.4 Hz, 6H), 3.05−3.12 (m, 1H),
5.03 (s, 2H), 6.91−6.96 (m, 2H), 7.06−7.07 (m, 2H), 7.41−7.49 (m,
6H), 7.77−7.81 (m, 4H); 13C NMR (100 MHz, CDCl3) δ 19.8, 32.8
(d, J = 2.9 Hz), 69.5, 103.6 (d, J = 114.3 Hz), 123.8, 124.9 (d, J = 3.8
Hz), 125.7, 127.6 (d, J = 7.3 Hz), 127.7, 128.5, 128.6, 131.2 (d, J = 8.0
Hz), 131.4 (d, J = 2.5 Hz), 131.6, 131.7, 135.1 (d, J = 105.3 Hz), 176.5
(d, J = 17.8 Hz); 31P NMR (162 MHz, CDCl3) δ 26.7; LC/MS m/z
375 [M + 1]+; HRMS (ESI) calcd for C24H23O2PNa [M + Na]+
397.1333, found 397.1334. Anal. Calcd for C24H23O2P: C, 76.99; H,
6.19. Found: C, 76.85; H, 6.23. This compound was crystallized from
dichloromethane/hexane (9/1) at 25 °C. An X-ray structure was
determined for this sample.
Compound 59. This product was synthesized from the allene 49
(0.21 g, 0.5 mmol). It was isolated by using an ethyl acetate/hexane
(4/1) mixture as the eluent: yield 0.20 g (93%); mp 160−162 °C
(white solid); IR (KBr, cm−1) 2975, 1555, 1453, 1437, 1250, 1188,
1121, 1028; 1H NMR (400 MHz, CDCl3) δ 1.72 (d, J = 6.8 Hz, 3H),
5.14−5.20 (m, 1H), 6.63 (d, J = 7.6 Hz, 1H), 6.97−7.01 (m, 1H),
7.16−7.26 (m, 4H), 7.38−7.80 (m, 13H); 13C NMR (100 MHz,
CDCl3) δ 19.5, 37.9, 105.0 (d, J = 118.4 Hz), 111.3, 121.1, 123.4,
124.3, 126.2, 127.9, 128.4, 128.6, 128.7, 128.8, 131.7, 131.8, 131.9,
132.2 (d, J = 13.5 Hz), 133.2 (d, J = 108.5 Hz), 133.3 (d, J = 108.3
Hz), 142.3, 154.4 (d, J = 11.5 Hz), 169.8 (d, J = 18.1 Hz); 31P NMR
(162 MHz, CDCl3) δ 21.6; LC/MS m/z 423 [M + 1]+; HRMS (ESI)
calcd for C28H24O2P [M + H]+ 423.1514, found 423.1514. Anal. Calcd
for C28H23O2P: C, 79.61; H, 5.49. Found: C, 79.48; H, 5.57.
Compound 64. This product was synthesized from the allene 54
(0.57 g, 1.3 mmol): yield 0.43 g (84%); mp 152−154 °C (white solid);
1
IR (KBr, cm−1) 2951, 1582, 1553, 1437, 1267, 1175, 1047; H NMR
Compound 60. This product was synthesized from the allene 50
(0.10 g, 0.3 mmol). It was isolated by using an ethyl acetate/hexane
(7/3) mixture: yield 0.09 g (88%); mp 102−104 °C (white solid); IR
(400 MHz, CDCl3) δ 1.30−1.31 and 1.53−1.58 (2 m, 8H), 3.02−3.09
(m, 1H), 5.03 (s, 2H), 6.95−7.01 (m, 2H), 7.07−7.08 (m, 2H), 7.40−
7.49 (m, 6H), 7.77−7.82 (m, 4H); 13C NMR (100 MHz, CDCl3) δ
26.5, 31.2, 43.8 (d, J = 3.3 Hz), 69.6, 104.4 (d, J = 114.8 Hz), 123.8,
124.8 (d, J = 3.9 Hz), 125.7, 127.5 (d, J = 7.2 Hz), 127.8, 128.5, 128.6,
131.3 (d, J = 7.8 Hz), 131.4 (d, J = 2.6 Hz), 131.6, 131.7, 135.2 (d, J =
105.3 Hz), 175.0 (d, J = 17.5 Hz); 31P NMR (162 MHz, CDCl3) δ
26.8; LC/MS m/z 401 [M + 1]+; HRMS (ESI) calcd for C26H26O2P
[M + H]+ 401.1670, found 401.1670.Anal. Calcd for C26H25O2P: C,
77.98; H, 6.29. Found: C, 77.85; H, 6.22.
1
(KBr, cm−1) 2957, 1555, 1454, 1437, 1312, 1254, 1182, 1121; H
NMR (400 MHz, CDCl3) δ 1.58 (br, 2H), 1.81−1.86 (m, 6H), 3.62−
3.67 (m, 1H), 6.62−6.64 (m, 1H), 6.97−7.00 (m, 1H), 7.18−7.21 (m,
1H), 7.45−7.58 (m, 7H), 7.72−7.77 (m, 4H); 13C NMR (100 MHz,
CDCl3) δ 26.2, 32.2, 38.2, 104.9 (d, J = 120.1 Hz), 111.0, 120.9, 123.2,
124.0, 128.6, 128.7, 131.7, 131.8, 132.1, 133.4 (d, J = 108.2 Hz), 154.1
(d, J = 11.7 Hz), 171.2 (d, J = 18.9 Hz); 31P NMR (162 MHz, CDCl3)
δ 21.7; LC/MS m/z 387 [M + 1]+; HRMS (ESI) calcd for C25H24O2P
[M + H]+ 387.1514, found 387.1514. Anal. Calcd for C25H23O2P: C,
77.70; H, 6.00. Found: C, 77.85; H, 5.93.
Compound 61. This product was synthesized from the allene 51
(0.10 g, 0.2 mmol). It was isolated by using an ethyl acetate/hexane
(7/3) mixture as the eluent: yield 0.09 g (90%); mp 150−152 °C
(white solid); IR (KBr, cm−1) 2926, 1551, 1454, 1314, 1256, 1179,
1119, 1042; 1H NMR (400 MHz, CDCl3) δ 1.10−1.26 (m, 3H),
1.65−1.74 (m, 7H), 2.92−2.98 (m, 1H), 6.84 (d, J = 7.6 Hz, 1H),
7.00−7.03 (m, 1H), 7.20−7.23 (m, 1H), 7.46−7.59 (m, 7H), 7.73−
7.78 (m, 4H); 13C NMR (100 MHz, CDCl3) δ 25.7, 25.9, 31.2, 37.2,
104.2 (d, J = 119.9 Hz), 110.9, 121.3, 123.2, 124.0, 128.6, 128.7, 131.7,
131.8, 132.1 (d, J = 2.6 Hz), 133.4 (d, J = 108.1 Hz), 154.0 (d, J = 11.5
Hz), 171.4 (d, J = 19.5 Hz); 31P NMR (162 MHz, CDCl3) δ 21.2;
LC/MS m/z 401 [M + 1]+; HRMS (ESI) calcd for C26H26O2P [M +
H]+ 401.1670, found 401.1670. Anal. Calcd for C26H25O2P: C, 77.98;
H, 6.29. Found: C, 78.12; H, 6.21. This compound was crystallized
from dichloromethane/hexane (9/1) at 25 °C. An X-ray structure was
determined for this sample.
Compound 65. This product was synthesized from the allene 55
(0.26 g, 0.6 mmol): yield 0.21 g (87%); mp 164−166 °C (white solid);
1
IR (KBr, cm−1) 2928, 1547, 1437, 1273, 1175, 1049; H NMR (400
MHz, CDCl3) δ 0.71−0.76 and 1.01−1.04 (2 m, 3H), 1.31−1.53 (m,
7H), 2.49−2.55 (m, 1H), 5.00 (s, 2H), 6.97−7.14 (m, 4H), 7.41−7.50
(m, 6H), 7.79−7.84 (m, 4H); 13C NMR (100 MHz, CDCl3) δ 25.6,
25.7, 29.8, 42.7, 69.3, 103.8 (d, J = 114.7 Hz), 123.8, 125.1, 125.7,
127.6 (d, J = 7.1 Hz), 127.8, 128.5, 128.6, 131.1 (d, J = 7.4 Hz), 131.4,
131.6, 131.7, 135.3 (d, J = 105.0 Hz), 174.9 (d, J = 18.1 Hz); 31P NMR
(162 MHz, CDCl3) δ 25.8; LC/MS m/z 415 [M + 1]+; HRMS (ESI)
calcd for C27H28O2P [M + H]+ 415.1827, found 415.1827. Anal. Calcd
for C27H27O2P: C, 78.24; H, 6.57. Found: C, 78.15; H, 6.63.
(b). Synthesis of Halobenzyl Products 66 and 67 from MOM-
Protected Allene 53. To a solution of allene 53 (0.20 g, 0.48 mmol) in
EtOAc (2 mL) was added 35% hydrochloric acid (1 mL), and the
contents were heated under reflux for 6 h. Water (10 mL) was added
after completion of the reaction (TLC). Then EtOAc (10 mL) was
added, the phases were separated, and the aqueous layer was extracted
with EtOAc. The organic layers were combined and washed with
saturated aqueous NaCl. After drying over Na2SO4, the solvent was
removed by using a rotary evaporator. The product 66 was purified by
column chromatography (silica gel; ethyl acetate/hexane 2/3).
Compound 67 was also prepared similarly.
(vii). Formation of 3,4-Disubstituted Isochromenes 62−65
and Halobenzyl Products 66 and 67 from MOM-Protected
Allenes 52−55. (a). Synthesis of 3,4-Disubstituted Isochromenes
62−65. To a solution of allene 52 (0.30 g, 0.77 mmol) in MeOH (2
mL) was added ZrCl4 (0.09 g, 0.38 mmol), and the contents were
heated under reflux for 6 h. Water (10 mL) was added after
completion of the reaction. Then EtOAc (10 mL) was added, the
phases were separated, and the aqueous layer was extracted with
Compound 66. Yield 0.17 g (88%); mp 148−150 °C (white solid);
1
IR (KBr, cm−1) 3241, 2976, 1609, 1439, 1225, 1161, 1117; H NMR
(400 MHz, CDCl3) δ 1.56 and 1.70 (2 s, 6H), 3.70 and 4.07 (2 d, J =
J
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11.5 Hz, 2H), 6.82−6.91 (m, 2H), 7.07−7.26 (m, 7H), 7.39−7.43 (m,
1H), 7.51−7.62 (m, 3H), 7.86−7.90 (m, 3H); 13C NMR (100 MHz,
CDCl3) δ 30.5, 31.2, 43.6, 71.0, 127.3 (d, J = 89.6 Hz), 127.6, 127.7,
128.0, 128.3 (d, J = 1.5 Hz), 128.5 (d, J = 106.5 Hz), 128.6, 128.7,
130.1 (d, J = 2.5 Hz), 130.4, 131.9, 132.3, 132.4, 132.5, 132.8, 132.9,
136.79, 136.82, 138.7 (d, J = 11.8 Hz), 163.2 (d, J = 5.4 Hz); 31P NMR
(162 MHz, CDCl3) δ 32.0; LC/MS m/z 411 [M + 1]+, 413 [M + 3]+;
HRMS (ESI) calcd for C24H24ClO2PNa [M + Na]+ 433.1100, found
433.1100. Anal. Calcd for C24H24ClO2P: C, 70.16; H, 5.89. Found: C,
70.25; H, 5.81. This compound was crystallized from dichloro-
methane/hexane (9/1) at 25 °C. An X-ray structure was determined
for this sample.
AUTHOR INFORMATION
Corresponding Author
*Fax: (+91)-40-23012460. E-mail: kckssc@yahoo.com;
kckssc@uohyd.ernet.in.
■
Notes
The authors declare no competing financial interest.
ACKNOWLEDGMENTS
■
We acknowledge the Department of Science and Technology
(DST), New Delhi, India, and the University Grants
Commission, New Delhi, India, for funding and equipment.
K.V.S. thanks the Council of Scientific and Industrial Research
(CSIR), New Delhi, India, for a fellowship. K.C.K.S. also thanks
the DST for a J. C. Bose Fellowship.
Compound 67. This product was synthesized from the allene 53
(0.20 g, 0.48 mmol) and concentrated HBr (1 mL): yield 0.19 g
(85%); mp 170−172 °C (white solid); IR (KBr, cm−1) 3262, 2926,
1
1605, 1437, 1225, 1163, 1117; H NMR (400 MHz, CDCl3) δ 1.55
and 1.71 (2 s, 6H), 3.63 and 3.91 (2 d, J ≈ 9.8 Hz, 2H), 6.79−6.81 (m,
1H), 6.88−7.24 (m, 9H), 7.37−7.60 (m, 4H), 7.84−7.89 (m, 2H); 13C
NMR (100 MHz, CDCl3) δ 30.5, 31.2, 31.3, 71.1 (d, J = 4.5 Hz),
127.3 (d, J = 89.7 Hz), 127.5, 127.7, 128.1, 128.4, 128.6, 128.7, 129.1,
130.3, 130.8, 131.7, 131.9, 132.4 (d, J = 7.8 Hz), 132.5, 132.8 (d, J =
8.5 Hz), 137.0, 138.6 (d, J = 11.6 Hz), 162.7 (d, J = 5.3 Hz); 31P NMR
(162 MHz, CDCl3) δ 32.3; LC/MS m/z 455 [M + 1]+, 457 [M + 3]+;
HRMS (ESI) calcd for C24H25BrO2P [M + H]+ 455.0775, found
455.0778. Anal. Calcd for C24H24BrO2P: C, 63.31; H, 5.31. Found: C,
63.21; H, 5.39.
X-ray Data. X-ray data for compounds 26, 38, 46, 61, 63, and 66
were collected using Mo Kα (λ = 0.710 73 Å) radiation. The structures
were solved and refined by standard methods.17 The CCDC numbers
are CCDC 871308−871313.
REFERENCES
■
(1) (a) Ma, S. Acc. Chem. Res. 2003, 36, 701. (b) Modern Allene
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́ ̌
ez, F.; Mascarenas, J. L. Chem.
Crystal Data. 26: C22H27O7P, M = 434.41, monoclinic, space
group P21/c, a = 13.0951(10) Å, b = 9.4194(7) Å, c = 20.0552(12) Å,
β = 117.713(4)°, V = 2190.0(3) Å3, Z = 4, μ = 0.166 mm−1, 3836/0/
276 data/restraints/parameters, R indices (I > 2σ(I)) R1 = 0.0498 and
wR2 (all data) = 0.1268, CCDC No. 871308.
38: C24H21O2P, M = 372.38, monoclinic, space group P21/c, a =
6.6332(6) Å, b = 19.8814(18) Å, c = 15.5910(14) Å, β = 105.794(8)o,
V = 1978.5(3) Å3, Z = 4, μ = 0.154 mm−1, 3465/0/246 data/
restraints/parameters, R indices (I > 2σ(I)) R1 = 0.0518 and wR2 (all
data) = 0.1307, CCDC No. 871309.
(2) (a) Gu, Y.; Hama, T.; Hammond, G. B. Chem. Commun. 2000,
395. (b) Scheufler, F.; Maier, M. E. Eur. J. Org. Chem. 2000, 3945.
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(d) Kitagaki, S.; Okumura, Y.; Mukai, C. Tetrahedron 2006, 62, 10311.
(e) Yu, F.; Lian, X.; Ma, S. Org. Lett. 2007, 9, 1703. (f) Guo, H.; Qian,
R.; Guo, Y.; Ma, S. J. Org. Chem. 2008, 73, 7934. (g) Jiang, X.; Kong,
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Guo, H.; Qian, R.; Guo, Y.; Fu, C.; Ma, S. Tetrahedron 2009, 65, 4877.
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X.; Zhao, J.; Yu, Y.; Ma, S. J. Org. Chem. 2009, 74, 1130.
46: C21H17O2P, M = 332.32, monoclinic, space group P21/c, a =
12.678(2) Å, b = 17.397(3) Å, c = 17.716(5) Å, β = 114.278(18)°, V =
3561.9(13) Å3, Z = 8, μ = 0.163 mm−1, 5114/0/439 data/restraints/
parameters, R indices (I > 2σ(I)) R1 = 0.0426 and wR2 (all data) =
0.0916, CCDC No. 871310.
(3) Selected references: (a) Ishar, M. P. S.; Kumar, K.; Kaur, S.;
Kumar, S.; Girdhar, N. K.; Sachar, S.; Marwaha, A.; Kapoor, A. Org.
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Murphree, S. S. J. Org. Chem. 2003, 68, 6238. (c) Mukai, C.; Ohta, M.;
́
Yamashita, H.; Kitagaki, S. J. Org. Chem. 2004, 69, 6867. (d) Gonzalez-
́
61: C H O P, M = 400.43, triclinic, space group P1, a = 9.892(3)
̅
Cantalapiedra, E.; de Frutos, O.; Atienza, C.; Mateo, C.; Echavarren, A.
M. Eur. J. Org. Chem. 2006, 1430. (e) Alcaide, B.; Almendros, P.;
Aragoncillo, C.; Redondo, M. C.; Torres, M. R. Chem. Eur. J. 2006, 12,
26 25
2
Å, b = 11.884(4) Å, c = 18.630(6) Å, α = 97.442(5)°, β = 98.266(6)°,
γ = 90.151(5)°, V = 2148.6(12) Å3, Z = 4, μ = 0.147 mm−1, 7550/0/
523 data/restraints/parameters, R indices (I > 2σ(I)): R1 = 0.0674,
wR2 (all data) = 0.1789. CCDC no. 871311.
1539. (f) Panossian, A.; Fleury-Bregeot, N.; Marinetti, A. Eur. J. Org.
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Chem. 2008, 3826. (g) Cheong, P. H.-Y.; Morganelli, P.; Luzung, M.
R.; Houk, K. N.; Toste, F. D. J. Am. Chem. Soc. 2008, 130, 4517.
(h) Beccalli, E. M.; Bernasconi, A.; Borsini, E.; Broggini, G.;
Rigamonti, M.; Zecchi, G. J. Org. Chem. 2010, 75, 6923. (i) Wang,
T.; Ye, S. Org. Lett. 2010, 12, 4168. (j) Sun, Y.-W.; Guan, X.-Y.; Shi, M.
Org. Lett. 2010, 12, 5664. (k) Schuler, M.; Voituriez, A.; Marinetti, A.
Tetrahedron: Asymmetry 2010, 21, 1569. (l) Guan, X.-Y.; Shi, M. ACS
Catal. 2011, 1, 1154. (m) Poonoth, M.; Krause, N. J. Org. Chem. 2011,
76, 1934. (n) Inuki, S.; Iwata, A.; Oishi, S.; Fujii, N.; Ohno, H. J. Org.
Chem. 2011, 76, 2072. (o) Cheng, J.; Jiang, X.; Ma, S. Org. Lett. 2011,
13, 5200. (p) Szeto, J.; Sriramurthy, V.; Kwon, O. Org. Lett. 2011, 13,
5420. (q) Sajna, K. V.; Kotikalapudi, R.; Chakravarty, M.; Bhuvan.
Kumar, N. N.; Kumara Swamy, K. C. J. Org. Chem. 2011, 76, 920.
(r) Steurer, M.; Jensen, K. L.; Worgull, D.; Jørgensen, K. A. Chem. Eur.
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63: C24H23O2P, M = 374.39, Monoclinic, Space group P2(1)/c, a =
11.4961(7), b = 14.8975(11), c = 16.1208(12) Å, β = 132.778(4)o, V =
2026.5(2) Å3, Z = 4, μ = 0.151 mm−1, data/restraints/parameters:
3525/0/246, R indices (I > 2σ(I)) R1 = 0.0584 and wR2 (all data) =
0.1145, CCDC No. 871312.
66: C24H24ClO2P, M = 410.85, orthorhombic, space group Pna21, a
= 17.5578(8) Å, b = 8.6412(4) Å, c = 28.8289(17) Å, V = 4373.9(4)
Å3, Z = 8, μ = 0.264 mm−1, 4599/0/509 data/restraints/parameters, R
indices (I > 2σ(I)) R1 = 0.0397 and wR2 (all data) = 0.0893, CCDC
No. 871313.
ASSOCIATED CONTENT
■
S
* Supporting Information
(4) (a) Chakravarty, M.; Kumara Swamy, K. C. J. Org. Chem. 2006,
71, 9128. (b) Chakravarty, M.; Bhuvan Kumar, N. N.; Sajna, K. V.;
Kumara Swamy, K. C. Eur. J. Org. Chem. 2008, 4500. (c) Phani Pavan,
M.; Chakravarty, M.; Kumara Swamy, K. C. Eur. J. Org. Chem. 2009,
5927. (d) Bhuvan Kumar, N. N.; Nagarjuna Reddy, M.; Kumara
Figures and CIF files giving ORTEP drawings, copies of
1H/13C NMR spectra of all new products, and crystal data for
26, 38, 46, 61, 63, and 66. This material is available free of
charge via the Internet at http://pubs.acs.org.
K
dx.doi.org/10.1021/jo300705f | J. Org. Chem. XXXX, XXX, XXX−XXX

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