Propyne iminium salts and phosphorus(III) nucleophiles: Synthesis of (3-morpholinoallenyl)phosphanes and -phosphane oxides or 1-(morpholinopropargyl)phosphanes and -phosphonates

Article abstract of DOI:10.1002/ejoc.200300080

Treatment of 4-(1,3-diphenyl-l-propynylidene)morpholinium triflate (1a) with the neutral phosphorus nucleophiles Me₃Si-PPh₂, Me₃Si-P(Ph)C₅H₁₁, and Me₃SiO-PPh₂ affords (3-morpholinoallenyl)phosphanes 4 and 5 and (3-morpholinoallenyl)phosphane oxide 11, respectively. In contrast to these conjugate addition reactions at the ambident propyne iminium moiety of 1a, nucleophilic attack by Me₃Si-PEt₂ and Me₃SiO-P(OEt)₂ takes place at the iminium function and gives (1-morpholinopropargyl)phosphane 6 and (1-morpholinopropargyl)phosphonate 12, respectively. Propyne iminium salt 1b reacts with Me₃Si-PPh₂ to form (3-morpholino-1,3-butadienyl)phosphane oxide 8. The bis(donor)-substituted allene 4 is transformed by oxidation of the phosphorus substituent into the push-pull substituted allenylphosphane oxide 11. Treatment of allene 4 with elemental sulfur results in the formation of betaine 16, which undergoes [3+2] cycloaddition reactions with acetylenic esters to afford 5-benzylidene-4,5-dihydrothiophenes 17 and 18. Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003.

Full text of DOI:10.1002/ejoc.200300080

FULL PAPER
Propyne Iminium Salts and Phosphorus(III) Nucleophiles:
Synthesis of (3-Morpholinoallenyl)phosphanes and -phosphane Oxides or
1-(Morpholinopropargyl)phosphanes and -phosphonates
Martin Reisser,[a] Alexandra Maier,[a] and Gerhard Maas*[a]
Keywords: Allenes / Betaines / Iminium salts / Nucleophilic additions / Organophosphorus compounds
Treatment of 4-(1,3-diphenyl-l-propynylidene)morpholinium
triflate (1a) with the neutral phosphorus nucleophiles
Me3Si−PPh2, Me3Si−P(Ph)C5H11, and Me3SiO−PPh2 affords
(3-morpholinoallenyl)phosphanes 4 and 5 and (3-morpholi-
noallenyl)phosphane oxide 11, respectively. In contrast to
these conjugate addition reactions at the ambident propyne
iminium moiety of 1a, nucleophilic attack by Me3Si−PEt2 and
salt 1b reacts with Me3Si−PPh2 to form (3-morpholino-1,3-
butadienyl)phosphane oxide 8. The bis(donor)-substituted
allene 4 is transformed by oxidation of the phosphorus sub-
stituent into the push-pull substituted allenylphosphane ox-
ide 11. Treatment of allene 4 with elemental sulfur results in
the formation of betaine 16, which undergoes [3+2] cycload-
dition reactions with acetylenic esters to afford 5-benzylid-
Me3SiO−P(OEt)2 takes place at the iminium function and ene-4,5-dihydrothiophenes 17 and 18.
gives (1-morpholinopropargyl)phosphane 6 and (1-morpholi- ( Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim,
nopropargyl)phosphonate 12, respectively. Propyne iminium
Germany, 2003)
Introduction
nation to the triple bond in the case of cuprates may over-
ride this simplistic explanation.
In continuation of these studies, we have investigated the
reactions between propyne iminium salts and several phos-
phorus() nucleophiles, and we report here that the regiose-
lectivity of the nucleophilic attack once more depends in a
delicate manner on the nature of the nucleophilic reagent.
Propyne iminium salts, featuring an iminium function in
conjugation with a carbonϪcarbon triple bond, represent
interesting building blocks for organic synthesis. Besides the
cycloaddition potential of the activated CϵC bond,[1] ad-
dition of nucleophiles to the conjugated system determines
the reactivity pattern. Because of the ambidentate nature of
the propyne iminium unit, nucleophiles can either react at
the iminium carbon atom (C-1 attack) to give propargylam-
ines or enter into conjugate addition (C-3 attack), from
which aminoallenes result. Thus, organolithium and -mag-
nesium compounds engage both in C-1 and in C-3 attack,[2]
while organocuprate addition reliably provides amino-
allenes.[3] For S- and N-nucleophiles, we found that the re-
gioselectivity was dependent on the nature of the nucleo-
phile.[4] The results obtained with hetero-nucleophiles are
by and large in agreement with the following interpretation:
under kinetic control, both charge- and orbital-control
favor C-1-attack but the reversibility of this reaction may
finally provide the isomeric, thermodynamically more
stable, aminoallenes.[4] We indeed found that a propargylic
S,N-acetal formed under kinetic control underwent a pro-
ton-catalyzed rearrangement to a 3-(alkylthio)-1-morpholi-
noallene under thermodynamic control. However, other
mechanistic details such as steric effects or metal coordi-
Results and Discussion
Silylated phosphanes react with α,β-unsaturated ketones
or aldehydes to furnish, in general, products resulting from
the conjugate addition of the nucleophilic phosphorus
unit.[5]
Analogously,
(trimethylsilyl)phosphanes
Me3SiϪPR2 (PR2 ϭ PPh2, PEt2, 1-phospholanyl) undergo
nucleophilic addition across the triple bond of acetylenic
ketones.[6] It was therefore of interest to know whether silyl-
phosphanes would behave analogously towards propyne
iminium moieties. The reaction between propyne iminium
triflate 1a and diphenyl(trimethylsilyl)phosphane (2a) was
investigated first, and after some experimentation, the fol-
lowing procedure was established (Scheme 1). A solution of
the propyne iminium salt 1a and anhydrous lithium chlo-
ride in THF was cooled to Ϫ78 °C and silylphosphane 2a
was added. The solution was brought to 20 °C over 12 h,
the solvent was removed, and the residue was extracted first
with pentane and then with toluene. From the toluene ex-
tract, 1-morpholino-3-(diphenylphosphanyl)allene 4 was
obtained in good yield. This procedure was also used for
the other nucleophilic addition reactions shown in Schemes
1 and 2.
[a]
Division of Organic Chemistry I, University of Ulm,
Albert-Einstein-Allee 11, 89081 Ulm, Germany
Fax: (internat.) ϩ 49-(0)731/5022803
E-mail: gerhard.maas@chemie.uni-ulm.de
Eur. J. Org. Chem. 2003, 2071Ϫ2079
DOI: 10.1002/ejoc.200300080
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M. Reisser, A. Maier, G. Maas
FULL PAPER
Scheme 2. Formation of a 2-dienamine from propyne iminium
salt 1b
7 could not be isolated, due to its rapid rearrangement into
1-(diphenylphosphanyl)-3-morpholino-1,3-butadiene 8. The
tautomeric 1,3-H shift is typical of aminoallenes bearing a
CH substituent at either terminus of the allene unit and
often prevents the isolation of these particular aminoall-
enes.[2]
It was fortunate that products 4, 5, and 8 could be iso-
lated from the reaction mixture in almost pure form simply
by toluene extraction, since the high hydrolytic lability of
their enamine functionalities prevented chromatographic
separation (see below).
Scheme 1. Reaction between propyne iminium salt 1a and phos-
phanes Me3SiϪPR2
If charge control were the dominant factor in the reaction
between salt 1a and anionic phosphorus nucleophiles, the
addition of the diphenylphosphide anion could be expected
to occur at the iminium carbon atom, resulting in the for-
mation of P,N-acetal 9. However, this product was not iso-
lated when salt 1 was added to a THF solution of KPPh2,
generated in situ from chlorodiphenylphosphane and pot-
assium, and allowed to react between Ϫ78 and 20 °C. NMR
spectra and TLC indicated a rather complex product mix-
ture, from which only one product could be isolated in pure
form after chromatographic separation. This product was
identified by a single-crystal X-ray structure analysis
(Figure 1) as the 4-(morpholino)hex-2-en-5-yn-1-one 10
It is reasonable to assume that conjugated nucleophilic
addition of silylphosphane 2a initially produces the phos-
phonio-substituted aminoallene 3 (Scheme 1), which is con-
verted into neutral allene 4 by chloride-induced desilylation,
generating volatile chloro(trimethyl)silane and lithium trifl-
ate. In fact, when the reaction was carried out in the ab-
sence of LiCl, a 31P NMR signal at δ ϭ 11.2 ppm was ob-
served; it can be attributed to phosphonium salt 3 [com-
pare: δ ϭ 11.6 ppm for the ion MePh2Pϩ[(Z)-CHϭ
CHPh)[7]] and disappears upon addition of LiCl. In the ab-
sence of LiCl, 3 slowly transformed over several days into
allene 4. However, salt 3 could not be isolated: removal of
the solvent furnished a black oil, from which no defined
compound could be isolated by extraction or distillation. It
is likely that the highly electrophilic trimethylsilyl triflate,
formed under these conditions, reacts with the enamine
function of allene 4 and eventually initiates oligomeriz-
ation.
Propyne iminium salt 1a was also treated with two other
silylphosphanes (Scheme 2). In analogy with the diphenyl-
substituted phosphane 2a, treatment with pentyl-phenyl-
(trimethylsilyl)phosphane (2b) gave (3-morpholinoallenyl)-
phosphane 5 (ca. 2:1 mixture of diastereomers) in good
yield, but treatment with diethyl(trimethylsilyl)phosphane
(2c) cleanly produced the (1-morpholinopropargyl)phos-
phane 6. Thus, the replacement of two phenyl groups in
the phosphorus nucleophile by two ethyl moieties causes a
regioselectivity switch from C-3 to C-1 attack.
Figure 1. Structure of 10 in the crystal (ORTEP plot); ellipsoids of
thermal vibration are shown at the 20% probability level; hydrogen
atoms are omitted except for the olefinic H2; selected bond lengths
Silylphosphane 2a also underwent conjugate addition
with the 1-methyl-substituted propyne iminium salt 1b
(Scheme 2). In this case, however, the expected aminoallene O1ϪC1ϪC2ϪC3 Ϫ130.4(2)
˚
[A] and torsion angles [°]: C1ϪO1 1.222(2), C1ϪC2 1.483(3),
C2ϪC3
1.332(2),
C4ϪC5
1.486(3),
C5ϪC6
1.192(2);
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Propyne Iminium Salts and Phosphorus(III) Nucleophiles
FULL PAPER
Scheme 4. Reaction between propyne iminium salt 1a and an
O-silyl phosphonite or phosphite
salt, which undergoes a MichaelisϪArbuzov type chloride-
induced desilylation (with elimination of Me3SiCl) ac-
companied by PIII Ǟ PV conversion.
Scheme 3. Reaction between propyne iminium salts 1a and 1b and
potassium (or lithium) diphenylphosphide
(Scheme 3). It is obvious that 10 results from two cationic
Trimethylsilyl phosphite 2e also underwent
a
units of salt 1, and it is likely that the 3-oxo-propenyl part MichaelisϪArbuzov-type reaction with 1a, but in this case
of the molecule originates from a (morpholino)allene unit the nucleophilic attack occurred at the iminium carbon
undergoing hydrolysis during chromatographic workup. atom and the (1-morpholinopropargyl)phosphonic acid es-
Provided that this assumption is correct, the formation of ter 12 was obtained in 75% yield (Scheme 4). The same
10 would include bond formation between the C-1 position transformation was achieved in almost equal yield (69%)
of one propyne iminium cation and the C-3 position of an- when diethyl phosphite (2f), rather than its derivative 2e,
other, and so between two acceptor positions. It may be was applied in the presence of a tertiary amine. The reac-
speculated that the diphenylphosphide anion is involved in tion between 1a and 2e is closely related to the recently
an umpolung step but the detailed mechanism is not yet reported formation of 1-amino-2-alkenyl phosphonates
known. When KPPh2 was replaced by NaPPh2 or LiPPh2, from the propene iminium salt PhCHϭCHCHϭNϩMe2
compound 10 was also formed but it appeared that the re- ClϪ and trialkyl phosphites.[10]
action was even less clean than in the first case.
In the hard and soft acids and bases model, neutral R3P
As expected, the diphenylphosphide anion behaved compounds rank as soft bases; the nucleophilicity decreases
towards propyne iminium salt 1b as a base rather than as a in the sequence R ϭ alkyl Ͼ aryl Ͼ alkoxy while the hard-
nucleophile. Treatment of 1b with LiPPh2 therefore gave N- ness of the phosphorus atom increases in the same order.[11]
[1-(phenylethynyl)vinyl]morpholine in 63% yield. We have If propyne iminium salts behaved as typical Michael ac-
reported previously that this deprotonation reaction can be ceptors, it would be expected that they would react with
performed conveniently with KOSiMe3 as a base.[8]
these nucleophiles preferentially by conjugate addition but
Silylated phosphinites and phosphites are also known to that reaction at the iminium carbon atom would become
undergo conjugate addition to α,β-unsaturated carbonyl more likely in the case of oxy-substituted phosphanes. The
compounds,[9] although 1,2-additions can occur as well likeliness of conjugate addition should therefore decrease in
(e.g., with acrolein[9b]). We found that they also add readily the order 2c Ͼ 2b Ͼ 2a Ͼ 2d Ͼ2e. We found, however, that
to propyne iminium salt 1a. Thus, O-trimethylsilyl phos- 2c reacts at C-1 of the propyne iminium unit rather than at
phinite 2d reacted with 1a in the presence of lithium chlo- C-3. On the other hand, all these phosphorus nucleophiles
ride to form (3-morpholinoallenyl)phosphane oxide 11 in would be expected to react under kinetic control at C-1,
good yield (Scheme 4). Unlike the allenylphosphanes 4 and according to the same regioselectivity for charge- and or-
5, the more polar allene 11 is no longer soluble in toluene bital-controlled reactions[4] (see Introduction). Comparison
and therefore could not be isolated by extraction. More po- of the bulkiness of these R3P nucleophiles may explain the
lar solvents (e.g. CH2Cl2) dissolve not only 11 but also some apparently conflicting results: although quantitative data
of the lithium triflate formed as a by-product, and again, for our silylated phosphane derivatives, such as the Tolman
the hydrolytic lability of 11 prevented its purification by angle[12] and the pyramidality at phosphorus,[13] are not
chromatography. The same allene could be prepared inde- available, it can be stated qualitatively that the bulkiness
pendently by oxidation of allenylphosphane 4 (see below).
decreases in the order 2a Ͼ 2b Ͼ 2d Ͼ 2e Ͼ 2c. In fact,
In mechanistic terms, the formation of 11 is related to the first three compounds in the series undergo conjugate
that of 4, shown in Scheme 1. Conjugate nucleophilic ad- addition, while the last two add to the iminium carbon
dition of 2d generates a trimethylsilyloxy-phosphonium atom. It may therefore be argued that, under kinetic con-
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M. Reisser, A. Maier, G. Maas
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trol, the phosphorus nucleophile preferentially approaches
the iminium function (as predicted by the calculated values
of atomic charge and LUMO coefficients[4]). However, since
bond formation at C-1 generates two adjacent, densely sub-
stituted, quaternary centers, it is either a reversible reaction
or completely inhibited energetically when the nucleophile
becomes too bulky; in this case, C-3 attack, thanks to its
less congested transition structure, can become more favor-
able energetically. In a quite different area, it has been
found that the kinetics of ligand substitution of transition-
metal carbonyls by phosphane derivatives depend both on
electronic factors and on the bulkiness of the latter spec-
ies.[14]
Since seemingly small changes in the R2PϪZ compound
can alter the regioselectivity of the nucleophilic addition, it
is not surprising that the exact nature of the propyne imin-
ium moiety can have a similar effect. It is to be expected
that a lower degree of charge stabilization in the iminium
function should favor the formation and isolation of the
Scheme 6. Reagents and conditions: a) H2O, acetone, 75% yield. b)
(Me3SiO)2, CH2Cl2. c) S8, CH2Cl2, 91%. d) RCϵCCO2Me, 50 °C,
24 h (RϭH: 61%; R ϭ CO2Me: 41%)
product of nucleophilic addition at this position, since the Treatment with bis(trimethylsilyl)peroxide gave the allenyl-
reversibility of the addition is less likely. We indeed found phosphane oxide 11. In spite of careful exclusion of moist-
that Me3SiOPPh2/LiCl reacts with propyne iminium salt 13 ure, the NMR spectra of the latter showed the presence of
(Scheme 5) to give an inseparable mixture of the propargyl- morpholine (ca. 5Ϫ6%), indicative of partial hydrolysis of
and the allenylphosphane oxide, in which the former com- the enamine function. The simultaneous presence of the re-
pound dominated by far. In contrast, the isomeric iminium sulting α,β-unsaturated ketone was not fully established by
salt 14 gave only the conjugate addition product (i.e., the the NMR spectra, since most signals were covered by those
allenylphosphane oxide), in complete analogy with 1a and of the allene, but was clearly shown by the expected molecu-
several other related salts possessing a well-stabilized N,N- lar ion peaks in the mass spectra of 11.
dialkyliminium function.[15]
On the other hand, elemental sulfur did not only oxidize
the P atom but also reacted with the nucleophilic enamine
function, resulting in the formation of betaine 16, which
formed completely stable, bright ruby-red crystals. Reac-
tions between enamines and S8 have been known for some
time,[19] and related dipolar iminium sulfides have been iso-
lated in cases in which the positive charge was delocalized
in a tetraalkylamidinium unit.[20] A similar betaine was pos-
tulated as an intermediate in reactions between push-pull
substituted 1,1-diethoxyallenes and sulfur.[21]
The constitution and the double bond configuration of
16 were confirmed by an X-ray crystal structure determi-
nation (Figure 2). Notably, the π systems of the CϭC and
the CϭNϩ bond are no longer in conjugation but are al-
Scheme 5. Isomeric propyne iminium salts displaying different re-
gioselectivity for nucleophilic addition of Me3SiϪOPPh2
The chemistry of the novel electron-rich (3-morpholi- most orthogonal to each other. Also interesting is the small
noallenyl)phosphanes 4 and 5 would be expected to be bond angle C1ϪC2ϪS1 (106.1°), which may indicate some
dominated by transformations of the two reactive func- degree of attractive electrostatic interaction between the
tionalities: the enamine moiety[16] and the (allenyl)phos- anionic sulfur and the cationic iminium function; however,
phane unit.[17] This was confirmed by some transformations no pyramidalization of the iminium carbon C1 is seen. On
carried out with allene 4 (Scheme 6). The high hydrolytic the other hand, steric repulsion with the substituents at the
lability of 4 has already been mentioned; in fact, it was re- opposite end of the double bond is also likely to contribute
adily hydrolyzed in contact with water to form the 3-(di- to the angle deformation at C2, resulting in compression of
phenylphosphanyl)prop-2-en-1-one 15. Only one dia- angle C1ϪC2ϪS1 and widening of the two other bond
stereomer was isolated, to which the E configuration was angles.
assigned from the small values of the phosphorus coupling
Betaine 16 was found to undergo a dipolar [3ϩ2] cyclo-
of the olefinic proton (3JH,P ϭ 3.5 Hz, cis-coupling) and of addition reaction with methyl propiolate, as well as with
the carbonyl carbon atom (3JC,P ϭ 2.7 Hz, trans coup- dimethyl acetylenedicarboxylate, to give the 5-benzylidene-
ling).[7]
4,5-dihydrothiophenes 17 and 18, respectively (Scheme 6).
Oxidation of the λ3-phosphorus of 4 to give the corre- The structure of 18 was also established by an X-ray crystal
sponding λ5-phosphorus compounds was also possible.[18] structure analysis (Figure 3). For 17, an analogous structure
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Propyne Iminium Salts and Phosphorus(III) Nucleophiles
FULL PAPER
Table 1. Selected NMR spectroscopic data of (morpholinoallenyl)-
phosphanes and -phosphoryl compounds, morpholino(Ph)C3ϭ
C2ϭC1(Ph)R
Allene
R
δ(C1) [ppm]
(1JC,P, [Hz])
δ(C2) [ppm]
(2JC,P [Hz])
δ(P)
[ppm]
4
PPh2
P(Ph)Pent
111.8 (19)
112.8 (22)
113.2 (22)
110.0 (101)
205.7 (Ϫ)
202.6 (Ϫ)
202.2 (Ϫ)
210.3 (5.3)
Ϫ7.1
Ϫ19.1
Ϫ19.9
29.5
5[a]
11
P(ϭO)Ph2
[a]
Two diastereomers.
ily achieved through their 13C NMR spectra (Table 1). The
chemical shifts of the central allenic carbon atom [δ(C2)]
are diagnostic. Τhey are very close to those of other fully
substituted aminoallenes,[2b,3d] and they indicate that the
shielding effect of the PR2 groups on this carbon atom is
small. Replacement of these substituents by an electron-
withdrawing phosphoryl group results in the expected de-
shielding of the central allenic carbon atom, but again the
effect is small (δ ϭ 4.6 ppm for the change from 4 to 11,
for example). IR spectroscopy is not suited to identification
of the allenic or propargyl reaction products. No CϵC
stretching vibration was observed for 6 and 12, and the Cϭ
CϭC valence vibrations of the allenes, expected as weak
and broad absorption(s) in the 1880Ϫ1920 cmϪ1 rang-
e,[2b,3d,18] were either too weak to be observed or coincided
with overtones of the aromatic rings.
Figure 2. Structure of 16 in the crystal (ORTEP plot); ellipsoids of
thermal vibration are shown at the 20% probability level; hydrogen
˚
atoms are not shown; selected bond lengths [A] and angles [°]:
C1ϪN 1.310(2), C1ϪC2 1.488(3), C2ϪC3 1.354(3), C3ϪP
1.803(2), C2ϪS1 1.715(2), PϪS2 1.960(1); C1ϪC2ϪC3 126.4(2),
C1ϪC2ϪS1 106.1(1), C3ϪC2ϪS1 127.4(1), C2ϪC3ϪP 123.5(1);
torsion angles [°]: NϪC1ϪC2ϪS1 83.1(2), C4ϪC1ϪC2ϪC3
82.6(2), C2ϪC3ϪPϪS2 36.0(2)
Conclusion
Propyne iminium salts are ambident electrophiles capable
of reacting with phosphorus() nucleophiles either at the
iminium function (C-1 attack) or at the β-position of the
CϵC bond. The regioselectivity depends on both reaction
partners. Both reaction modes give interesting products: C-
1 attack allows the preparation of novel α-alkynyl-α-amino-
phosphonates, which may be of interest as bioisosters of
non-natural α-amino acid esters, while the conjugate ad-
dition affords 3-aminoallenylphosphanes and -phosphane
oxides, which constitute novel 1,3-bis(donor)- and push-
pull-substituted allenes, respectively. This method for the
preparation of phosphorus-substituted allenes is concep-
tually different from previous ones, which furnished allenyl-
Figure 3. Structure of 18 in the crystal (ORTEP plot); ellipsoids of
thermal vibration are shown at the 20% probability level; hydrogen
˚
atoms are not shown; selected bond lengths [A] and angles [°]:
C1ϪC2 1.332(5), C2ϪC3 1.535(5), C3ϪC4 1.566(5), C4ϪC5
1.353(5), C5ϪP 1.840(3), PϪS2 1.949(1); C1ϪS1ϪC4 92.4(2),
C3ϪC4ϪC5 134.1(3), S1ϪC4ϪC5 115.2(2), C4ϪC5ϪP 130.2(2),
C4ϪC5ϪC20 116.2(3)
is assumed on the basis of the similar shifts of carbon atoms phosphanes from allenyl anions and phosphorus electro-
C-4 and C-5 in the dihydrothiophene ring and of the P,C- philes,[18,22] and PO-substituted allenes from propargyl al-
5 coupling constant. The orientation of the unsymmetrical cohols and chlorophosphanes followed by [2,3] rearrange-
dipolarophile is derived from the presumed polar character ment.[23] We have presented some examples of further
of the cycloaddition reaction; it is also in accordance with transformations of the (3-morpholinoallenyl)phosphane 4,
5
the observation of a JH,P coupling (0.9 Hz) through a W- which illustrate that selective functionalization of either the
shaped bond geometry. Other dipolarophiles, such as maleic enamine or the (vinyl)phosphane functionality is possible.
anhydride, dimethyl fumarate and dimethyl maleate, did not We have reported elsewhere that dialkylaminoallenes are
react with 16 at 50 °C, while unspecific decomposition of converted thermally into condensed dihydroazepine deriva-
the betaine set in around 80 °C.
tives.[3c] In the cases of 4, 11, and related allenes, thermal
The identification of allenes 4, 5, and 11 and their dis- treatment results in either azepine or pyrrole derivatives.[15]
tinction from the isomeric propargyl compounds was read- These useful transformations will be reported in due course.
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M. Reisser, A. Maier, G. Maas
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27.83Ϫ28.03, 32.86Ϫ33.22 (2
51.4/51.1 (s, NCH2), 66.73 (s, OCH2), 112.8/113.2 (both d, JC,P
d
in all cases, C-1,-2,-3pentyl),
Experimental Section
1
ϭ
22 Hz, C-1allene), 126.6Ϫ137.2 (Caryl, NCϭ), 202.6/202.2 (C-2allene
)
General Remarks: Reactions were carried out in rigorously dried
glassware and under argon. Solvents were dried by standard pro-
cedures and kept under argon. The petroleum ether used had a
boiling point range of 30Ϫ60 °C. Column chromatography was
performed under hydrostatic conditions on silica gel (Si, 60,
0.063Ϫ0.2 mm, MachereyϪNagel) with distilled eluents; for flash
chromatography, pressurized nitrogen gas was applied. NMR spec-
tra: Bruker AMX 500 (1H: 500.14 MHz; 13C: 125.77 MHz; 31P:
202.48 MHz) and Bruker AC 200 (1H: 200.13 MHz; 13C:
50.32 MHz). CDCl3 was used as the solvent for all spectra. The
following references were applied: internal TMS for the proton
spectra (δ ϭ 0.00 ppm), the solvent signal for the 13C NMR spectra
[δ(CHCl3) ϭ 77.0 ppm], and external 85% H3PO4 (δ ϭ 0.00 ppm)
for the 31P spectra. IR spectra: PerkinϪElmer IR 883 spectrometer.
Mass spectra: Varian MAT 711 (FD) and Finnigan MAT SSQ 7000
(EI, FAB). Microanalyses: Elementar Vario EL, Division of Ana-
lytical Chemistry, University of Ulm. Melting points were deter-
mined in a Büchi apparatus according to Dr. Tottoli and are uncor-
rected.
ppm. 31P NMR: δ ϭ Ϫ19.1 (major), Ϫ19.9 (minor) ppm. MS (FD):
m/z (%) ϭ 455 (100) [Mϩ]. C30H34NOP (455.58).
Diethyl(1-morpholino-1,3-diphenyl-2-propynyl)phosphane (6):
A
solution of iminium salt 1a (3.40 g, 8.0 mmol) and anhydrous lith-
ium chloride (0.80 g, 18.9 mmol) in THF (30 mL) was cooled to
Ϫ78 °C. Diethyl(trimethylsilyl)phosphane (2c, 1.23 g, 8.0 mmol)
was added, and the mixture was brought to room temp. over 12 h.
The volatiles were evaporated, and ether (150 mL) was added to
the residue. After extraction with two portions of water (100 and
50 mL), the organic phase was dried (CaCl2), and the solvent was
evaporated. The residue was recrystallized from cyclohexane/ethyl
acetate to give clear, colorless crystals; yield: 2.05 g (70%); m.p. 112
°C. IR (KBr): ν˜ ϭ 1597 (m), 1485 (s), 1444 (s), 1263 (s), 1122 (s),
1
1112 (vs), 921 (s), 760 (s), 705 (s) cmϪ1. H NMR (500.14 MHz):
δ ϭ 0.83Ϫ1.21 (m, 9 H, PCH2CH3, PCH2, PCH), 1.62Ϫ1.64 (m,
1 H, PCH), 2.61 (mc, 2 H, NCH2), 2.97 (mc, 2 H, NCH2),
3.70Ϫ3.75 (m, 4 H, OCH2), 7.20Ϫ7.67 (10 Haryl) ppm. 13C{1H}
NMR (125.77 MHz): δ ϭ 10.3 (d, CH3), 11.1 (d, CH3), 18.1 (d,
3
J ϭ 18.9 Hz, PCH2), 19.3 (d, J ϭ 17.6 Hz, PCH2), 49.4 (d, JC,P ϭ
The following compounds were prepared by literature methods: im-
1
inium salts 1a and 1b;[24] phosphane derivatives 2a,[25] 2b,[26], 2c[27]
,
11. 3 Hz, NCH2), 67.4 (s, OCH2), 68.6 (d, JC,P ϭ 12.6 Hz, C-1),
2
3
2d,[28], and 2e.[9a,29] Anhydrous lithium chloride was obtained by
heating at 150 °C/0.04 mbar for 2 h.
86.2 (d, JC,P ϭ 7.6 Hz, C-2), 91.0 (d, JC,P ϭ 2.5 Hz, C-3), 123.1,
127.0, 128.1, 128.3, 131.7, 138.2, 138.3 (Caryl) ppm. 31P NMR: δ ϭ
9.4 ppm. MS (FD): m/z (%) ϭ 365 (3) [Mϩ], 276 (100) [Mϩ
Ϫ
(3-Morpholino-1,3-diphenyl-1,2-propadienyl)diphenylphosphane (4):
A solution of salt 1a (4.25 g, 10.0 mmol) and anhydrous lithium
chloride (0.80 g, 18.9 mmol) in anhydrous THF (50 mL) was cooled
to Ϫ78 °C. Diphenyl(trimethylsilyl)phosphane (2a, 2.58 g,
10 mmol) was added, and the mixture was brought to room temp.
over 12 h, whereupon its color changed to black. The volatiles were
evaporated, and the residue was triturated with pentane (30 mL) in
an ultrasonic bath to remove any components of low polarity. The
residue was then extracted with anhydrous toluene (3 ϫ 30 mL);
the extract was separated each time by filtration under argon. The
combined toluene extracts were evaporated to dryness, and anhy-
drous ether (30 mL) was added. After a short time, allene 4 started
to separate as a greenish-gray, microcrystalline solid, which could
not be purified further because of its hydrolytic lability; yield:
3.64 g (79%), m.p. 122 °C. IR (KBr): ν˜ ϭ 1595 (m), 1488 (s), 1446
PEt2]. C23H28NOP (365.45): calcd. C 75.59, H 7.72, N 3.83; found
C 75.92, H 7.77, N 3.73.
[(1E)-3-Morpholino-1-phenyl-1,3-butadienyl]diphenylphosphane (8):
The synthesis was performed as described for 4, from iminium salt
1b (1.82 g, 5.0 mmol), anhydrous lithium chloride (0.40 g,
9.4 mmol), and phosphane 2a (1.29 g, 5.0 mmol) in THF (50 mL).
A light brown oil was obtained; yield: 1.26 g (63%). IR (KBr): ν˜ ϭ
1650 (m), 1585 (m), 1425 (m), 1100 (m) cmϪ1
.
1H NMR
(500.14 MHz): δ ϭ 2.61 (mc, 4 H, NCH2), 3.21 (mc, 4 H, OCH2),
3
3.93 (s, 1 H, 4-H1), 3.97 (s, 1 H, 4-H2), 5.91 (d, JH,P ϭ 7.4 Hz, 1
H, 2-H), 7.0Ϫ7.6 (15 Haryl) ppm. 13C{1H} NMR (125.77 MHz):
δ ϭ 48.5 (s, NCH2), 66.0 (s, OCH2), 92.2 (s, C-4), 118.7Ϫ143.2
3
(Caryl, C-1,-2), 152.0 (d, JC,P ϭ 4.8 Hz, C-3) ppm. 31P NMR: δ ϭ
4.4 ppm. C26H26NOP (399.47): calcd. C 78.17, H 6.56, N 3.51;
found C 78.55, H 6.70, N 3.18.
(s), 1434 (s), 1232 (s), 1116 (vs), 766 (vs), 745 (s), 695 (vs) cmϪ1
.
1H NMR (500.14 MHz): δ ϭ 2.32Ϫ2.45 (m, 4 H, NCH2),
3.55Ϫ3.65 (m, 4 H, OCH2), 7.15Ϫ7.40 (m, 18 Haryl), 7.65Ϫ7.68 (m,
2 Haryl) ppm. 13C{1H} NMR (125.77 MHz): δ ϭ 50.8 (s, NCH2),
66.9 (s, OCH2), 111.8 (d, 1JC,P ϭ 19 Hz, C-1allene), 127.0Ϫ129.0 and
133.8Ϫ137.4 (Caryl, NCϭ), 205.7 (s, C-2allene) ppm. 31P NMR: δ ϭ
Ϫ7.1 ppm. MS (EI, 70 eV): m/z (%) ϭ 461 (2) [Mϩ], 276 (100) [Mϩ
Ϫ PPh2]. C31H28NOP (461.54): calcd. C 80.67, H 6.11, N 3.03;
found C 79.29, H 6.60, N 2.77.
(2E)-4-Morpholino-1,3,4,6-tetraphenylhex-2-en-5-yn-1-one
(10):
Potassium (0.20 g, 5.1 g-atom) and chloro(diphenyl)phosphane
(1.10 g, 5.0 mmol) were added successively to anhydrous THF
(200 mL), and the mixture was heated at reflux until the metal had
disappeared (3 h). The solution was cooled to Ϫ78 °C and solid
iminium salt 1a (2.13 g, 5.0 mmol) was added from a wide-bore
funnel. The mixture was brought to room temp. over 12 h, the sol-
vent was removed at 14 mbar, and the residue was subjected to
(3-Morpholino-1,3-diphenyl-1,2-propadienyl)(pentyl)phenylphos- flash column chromatography (silica gel, eluent: cyclohexane/ethyl
phane (5): The synthesis was performed as described for 4, from acetate, 5:1). An off-white solid was isolated from the second frac-
iminium salt 1a (2.44 g, 5.7 mmol), anhydrous lithium chloride tion and was recrystallized from cyclohexane to give 10 (0.20 g,
(0.40 g, 9.4 mmol), and pentyl-phenyl(trimethylsilyl)phosphane (2b,
17%), m.p. 168 °C. IR (KBr): ν˜ ϭ 1644, 1264, 1113, 694 cmϪ1
1.45 g, 5.7 mmol) in THF (50 mL). Allene 5 was obtained as a 1H NMR (500.14 MHz): δ ϭ 2.62Ϫ2.74 (m, broad, 2 H, NCH2),
.
light-brown oil, which was not analytically pure but could not be
2.88Ϫ3.05 (m, 2 H, NCH2), 3.87 (mc, 4 H, OCH2), 6.66 (d, J ϭ
8.4 Hz, 2 Haryl), 7.03Ϫ7.77 (several m, 18 Haryl), 7.71 (s, 1 H,
purified further due to its hydrolytic lability; yield: 2.10 g (80%).
IR (KBr): ν˜ ϭ 1666 (w), 1597 (m), 1488 (m), 1446 (s), 1299 (s), Holefin). 13C NMR (125.77 MHz): δ ϭ 49.4 (NCH2), 67.4 (OCH2),
1260 (s), 1233 (s), 1118 (vs), 762 (s), 744 (s), 697 (vs) cmϪ1 1H 74.0 (C-4), 84.9 and 92.5 (CϵC), 122.6, 126.2Ϫ129.4, 131.7, 132.7,
.
NMR (500.14 MHz): δ ϭ 0.82Ϫ2.00 (m, 11 Hpentyl), 2.66Ϫ2.85 (m, 137.0, 138.2, 139.0, 154.1, 193.3 (CϭO). MS (FAB, p-nitrobenzyl
4 H, NCH2), 3.75Ϫ3.87 (m, 4 H, OCH2), 7.15Ϫ7.85 (15 Haryl) ppm. alcohol): m/z (%) ϭ 484 (6) [Mϩ], 397 (19), 276 (100). C34H29NO2
13C{1H} NMR (125.77 MHz): δ (major/minor diastereomer) ϭ (483.61): calcd. C 84.44, H 6.04, N 2.90; found C 82.94, H 5.98,
13.68/13.74 (s, C-5pentyl), 21.99/22.06 (s, C-4pentyl), 25.33Ϫ25.66, N 2.60.
2076
 2003 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
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Eur. J. Org. Chem. 2003, 2071Ϫ2079

Propyne Iminium Salts and Phosphorus(III) Nucleophiles
FULL PAPER
3
(3-Morpholino-1,3-diphenyl-1,2-propadienyl)diphenylphosphane Ox-
ide (11). Method A: The synthesis was performed as described for
4 from iminium salt 1a (4.25 g, 10.0 mmol), anhydrous lithium
chloride (0.80 g, 18.9 mmol), and diphenyl(trimethylsilyloxy)phos-
phane (2d, 2.74 g, 10.0 mmol) in THF (50 mL). After evaporation
of the volatiles, a mixture of allene 11 and of lithium trifluorome-
thanesulfonate was obtained. This could not be completely sepa-
rated by extraction, but was suited for further transformations of
11.
JC,P ϭ 20.1 Hz), 155.5 (d, JC,P ϭ 25.1 Hz, C-3), 193.7 (d, JC,P
ϭ
2.7 Hz, C-1) ppm. 31P NMR: δ ϭ 4.3 ppm. C27H21OP (392.44):
calcd. C 82.64, H 5.39; found C 82.55, H 5.60.
(E)-1-(Diphenylthiophosphoryl)-3-(1,4-oxazinan-4-ium-4-ylidene)-
1,3-diphenyl-1-propene-2-thiolate (16): Allene 4 (4.62 g, 10.0 mmol)
was dissolved in dichloromethane (50 mL), and elemental sulfur
(0.64 g, 20.0 g-atom, carefully dried over P4O10) was added with
stirring. The solution quickly became orange-colored. After 2 h the
solvent was removed, and acetonitrile (20 mL) was added to the
residue. Betaine 16 separated as a microcrystalline, orange solid.
Recrystallization from a dichloromethane solution with a surface
layer of pentane gave well shaped, bright ruby red crystals; yield:
4.78 g (91%), m.p. 180 °C (dec.). IR (KBr): ν˜ ϭ 1596 (s), 1508
Method B: Bis(trimethylsilyl)peroxide (0.89 g, 5.0 mmol) was added
to a solution of allene 4 (2.31 g, 5.0 mmol) in CH2Cl2 (10 mL).
After the mixture had been stirred for 12 h, the volatiles were eva-
porated at 14 mbar. The pale yellow, solid residue consisted of al-
lene 11 contaminated with a compound that is likely to be the hy-
1
(s), 1436 (s), 1114 (s), 1100 (s), 711 (vs), 694 (vs) cmϪ1. H NMR
(500.14 MHz): δ ϭ 3.70Ϫ4.40 (m, 8 H, NCH2CH2O), 6.77 (d, J ϭ
6.7 Hz, 2 Haryl), 6.90Ϫ7.32 (m, 16 Haryl), 8.23 (d, J ϭ 7.9 Hz, 2
H
NCH2), 64.7, 65.0 (s, OCH2), 123.2Ϫ132.5 (Caryl), 139.1 (d, J ϭ
8.8 Hz), 167.7 (d, J ϭ 9.7 Hz), 173.3 (CϭNϩ) ppm. 31P NMR: δ ϭ
39.8 ppm. MS (FD): m/z ϭ 525 [Mϩ]. C31H28NOPS2 (525.66):
calcd. C 70.83, H 5.37, N 2.66; found C 70.87, H 5.35, N 2.67.
drolysis product (3-oxo-1,3-diphenyl-1-propenyl)diphenylphos-
2
phane oxide (ca. 6%) [13C{1H} NMR: δ ϭ 140.2 (d, JC,P
ϭ
aryl) ppm. 13C{1H} NMR (125.77 MHz): δ ϭ 52.4, 53.4 (s,
8.4 Hz), 193.3 (d, JC,P ϭ 17.1 Hz, CϭO) ppm. 31P NMR: δ ϭ
29.0 ppm]. Further purification of 11 was not possible, due to its
hydrolytic lability. 1H NMR (500.14 MHz): δ ϭ 2.40Ϫ2.58 (m, 4
H, NCH2), 3.55Ϫ3.65 (m, 4 H, OCH2), 7.16Ϫ7.72 (20 Haryl) ppm.
13C{1H} NMR (125.77 MHz): δ ϭ 50.3 (s, NCH2), 66.4 (s, OCH2),
3
1
110.0 (d, JC,P ϭ 100.6 Hz, C-1allene), 127.0Ϫ133.1 (Caryl, NCϭ),
Methyl 5-[(E)-1-(Diphenylthiophosphoryl)-1-phenylmethylidene]-4-
2
210.3 (d, JC,P ϭ 5.3 Hz, C-2allene) ppm. 31P NMR: δ ϭ 29.5 ppm.
morpholino-4-phenyl-4,5-dihydrothiophene-3-carboxylate (17):
A
solution of betaine 16 (2.62 g, 5.0 mmol) and methyl propiolate
(0.42 g, 5.0 mmol) in dichloromethane (20 mL) was placed in a
thick-walled Schlenk tube and heated at 50 °C for 24 h. The solvent
was evaporated, and the residue was subjected to column chroma-
tography (250 g of silica gel; eluent: cyclohexane/ethyl acetate, 1:1).
After recrystallization from the same solvent mixture, 1.85 g (61%)
of 17 was obtained as a yellow solid, which started to decompose
above 160 °C and melted at 201 °C. IR (KBr): ν˜ ϭ 1714 (vs, Cϭ
Diethyl (1-Morpholino-1,3-diphenyl-2-propynyl)phosphonate (12).
From 1a and 2e (Method A): The synthesis was carried out as de-
scribed above for 6, from iminium salt 1a (2.12 g, 5.0 mmol), lith-
ium chloride (0.40 g, 9.4 mmol), and diethoxy(trimethylsilyloxy)-
phosphane (2e, 1.05 g, 5.0 mmol). After crystallization from cyclo-
hexane/ethyl acetate, clear, colorless crystals were obtained (1.55 g,
75% yield); m.p. 132Ϫ133 °C.
O), 1573 (m), 1435 (m), 1285 (s), 1206 (s), 1113 (s), 694 (s) cmϪ1
.
From 1a and 2f (Method B): Diethyl phosphite (0.69 g, 5.0 mmol)
and ethyldiisopropylamine (0.65 g, 5.0 mmol) were added to a solu-
tion of salt 1a (2.12 g, 5.0 mmol) in dichloromethane (30 mL).
After stirring at room temp. for 12 h, the mixture was extracted
twice with water (100 and 50 mL). The organic layer was dried
(CaCl2), the solvent was evaporated, and the residue was recrys-
tallized as in method A; yield: 1.42 g (69%). IR (KBr): ν˜ ϭ 1486
(m), 1445 (m), 1245 (s, PϭO), 1114 (s), 1055 (s), 1022 (vs,
PϪOϪC), 960 (s), 698 (s) cmϪ1. 1H NMR (200.13 MHz): δ ϭ 1.11
1H NMR (500.14 MHz): δ ϭ 2.77 and 2.97 (2 mc, 4 H, NCH2),
3.51 (s, 3 H, OCH3), 3.98 and 4.19 (2 mc, 4 H, OCH2), 5.26 (d,
5JH,P ϭ 0.9 Hz, 1 H, 2-H), 6.70Ϫ7.37 (18 Haryl), 7.63 (d, J ϭ
6.0 Hz, 2 Haryl) ppm. 13C{1H} NMR (125.77 MHz): δ ϭ 49.8 (s,
NCH2), 51.4 (s, OCH3), 67.0 (s, OCH2), 82.2 (s, C-4), 126.7Ϫ143.5
2
(Caryl, 3 Colefin), 162.3 (CϭO), 165.3 (d, JC,P ϭ 9.8 Hz, C-5) ppm.
31P NMR: δ ϭ 40.5 ppm. MS (EI, 70 eV): m/z (%) ϭ 609 (8) [Mϩ],
524 (84) [Mϩ Ϫ C4H7NO], 392 (43) [Mϩ Ϫ Ph2PS]. C35H32NO3PS2
(609.74): calcd. C 68.94, H 5.29, N 2.30; found C 68.77, H 5.40,
N 2.21.
3
and 1.29 (each t, JH,H ϭ 7.0 Hz, 3 H, CH3), 2.50Ϫ2.65 and
2.90Ϫ3.10 (2 m, 4 H, NCH2), 3.40Ϫ4.25 (3 m, 4 H, POCH2), 3.75
(pseudo-t, 4 H, morpholineϪOCH2), 7.25Ϫ7.40 (m, 6 Haryl),
7.55Ϫ7.65 (m, 2 Haryl), 7.95Ϫ8.05 (m, 2 Haryl) ppm. 13C{1H} NMR
(50.32 MHz): δ ϭ 15.75 (d, 3JC,P ϭ 4.5 Hz, CH3), 15.97 (d, 3JC,P ϭ
Dimethyl 5-[(E)-1-(Diphenylthiophosphoryl)-1-phenylmethylidene]-4-
morpholino-4-phenyl-4,5-dihydrothiophene-2,3-dicarboxylate (18): A
solution of betaine 16 (2.62 g, 5.0 mmol) and dimethyl acetylene-
dicarboxylate (0.71 g, 5.0 mmol) in dichloromethane (20 mL) was
placed in a thick-walled Schlenk tube and heated at 50 °C for 24 h.
The solvent was evaporated, the residue was dissolved in the mini-
mum amount of ethyl acetate, and cyclohexane was added until the
solution became turbid. After some time, solid 18 separated as the
cyclohexane solvate, which strongly retained the solvate molecules.
When a chloroform solution of this material was slowly concen-
trated, well shaped yellow crystals of a chloroform solvate were
3
2
4.9 Hz), 48.9 (d, JC,P ϭ 7.0 Hz, NCH2), 63.39 (d, JC,P ϭ 8.8 Hz,
2
POCH2), 63.56 (d, JC,P ϭ 7.7 Hz, POCH2), 66.8 (s, OCH2), 69.1
1
2
(d, JC,P ϭ 162 Hz, C-1), 82.0 (d, JC,P ϭ 4.6 Hz, C-2), 91.2 (d,
3JC,P ϭ 9.3 Hz, C-3), 122.1, 127.6, 127.9, 128.0, 128.2, 128.9, 131.5,
136.1 (d) (Caryl) ppm. 31P NMR: δ ϭ 18.1 ppm. C23H28NO4P
(413.45): calcd. C 66.82, H 6.82, N 3.39; found C 66.81, H 6.84,
N 3.34.
(2E)-3-(Diphenylphosphanyl)-1,3-diphenyl-2-propen-1-one (15): Al-
lene 4 (2.54 g, 5.5 mmol) was dissolved in acetone (30 mL), and obtained; after being kept at 0.01 mbar/ 20 °C they had the compo-
water (1 mL) was added. The mixture was stirred for 12 h under
argon. Evaporation of the solvent at 15 mbar and of other volatile
components at 0.01 mbar, followed by recrystallization from cyclo-
sition 18·CHCl3; yield: 1.61 g (41%), m.p. 134 °C. IR (KBr): ν˜ ϭ
1731 (vs), 1613 (m), 1435 (s), 1276 (vs), 1247 (vs), 1113 (s), 704
1
(m), 693 (m) cmϪ1. H NMR (500.14 MHz): δ ϭ 2.95Ϫ3.10 (2 m,
hexane/ethyl acetate, afforded 1.62 g (75%) of 15 as yellow crystals, 4 H, NCH2), 3.52 (s, 3 H, OCH3), 3.73 (s, 3 H, OCH3), 4.01 and
m.p. 126Ϫ127 °C. IR (KBr): ν˜ ϭ 1662 (s, CϭO), 1435 (m), 1228 4.18 (2 mc, 4 H, OCH2), 6.68Ϫ7.33 (18 Haryl), 7.74 (d, J ϭ 7.5 Hz,
1
(s), 746 (s), 695 (vs) cmϪ1. H NMR (500.14 MHz): δ ϭ 6.25 (d, 2 Haryl) ppm. 13C{1H} NMR (125.77 MHz): δ ϭ 49.1 (s, NCH2),
3JH,P ϭ 3.5 Hz, 2-H), 6.98Ϫ7.61 (20 Haryl) ppm. 13C NMR 52.0 and 52.8 (OCH3), 66.7 (s, OCH2), 85.4 (s, C-4), 126.7Ϫ143.1
2
(125.77 MHz): δ ϭ 127.9Ϫ134.6 (Caryl, C-2), 137.4 (s), 138.9 (d,
(Caryl, 3 Colefin), 161.8, 163.3 (CϭO), 162.7 (d, JC,P ϭ 10.2 Hz, C-
Eur. J. Org. Chem. 2003, 2071Ϫ2079
www.eurjoc.org
 2003 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
2077

M. Reisser, A. Maier, G. Maas
FULL PAPER
Table 2. Data for X-ray diffraction structure determination of compounds 10, 16, and 18
10
16
18
[a]
Empirical formula
Molecular mass
Temperature [K]
Crystal size [mm]
Crystal system
Space group
C34H29NO2
483.58
293(2)
0.38 ϫ 0.30 ϫ 0.15
Monoclinic
P21/n
12.977(2)
10.074(1)
20.638(4)
90
91.79(2)
90
2696.6(8)
4
1.191
C31H28NOPS2
525.69
293(2)
0.70 ϫ 0.60 ϫ 0.60
Monoclinic
P21/n
12.689(4)
16.363(5)
14.201(4)
90
114.05(2)
90
2692.7(1)
8
1.297
0.24
C37H34NO5PS2 ϫ 1.8 CHCl3
667.77 (882.60)
293(2)
0.54 ϫ 0.38 ϫ 0.27
Triclinic
¯
P1
˚
a [A]
12.343(2)
12.598(2)
15.043(3)
74.14(2)
87.90(2)
68.68(2)
2091.0(7)
2
1.402
˚
b [A]
˚
c [A]
α [°]
β [°]
γ [°]
3
˚
V [A ]
Z
ρcalcd. [g cmϪ3
]
µ(Mo-Kα) [mmϪ1
θ range [°]
Index ranges
]
0.073
0.55
1.88Ϫ23.53
Ϫ14 Յ h Յ 14
Ϫ11 Յ k Յ 11
Ϫ23 Յ l Յ 23
16125
1.82Ϫ24.27
Ϫ14 Յ h Յ 13
0 Յ k Յ 18
0Յ l Յ 16
23229
1.78Ϫ24.15
Ϫ14 Յ h Յ 13
Ϫ14 Յ k Յ 14
Ϫ17 Յ l Յ 17
13464
Reflections collected
Independent reflections (Rint
)
4006 (0.0592)
100
4006/ 0/334
0.810
4258 (0.0501)
97.9
4258/ 0/349
0.821
6232 (0.0333)
93.2
6232/0/491
1.050
Completeness of data set [%]
Data/restraints/parameters
Goodness-of-fit on F2
Final R indices [I Ͼ 2σ(I)]; R1, wR2
R indices (all data); R1, wR2
0.0382, 0.0826
0.0782, 0.0918
0.10, Ϫ0.11
0.0296, 0.0582
0.0536, 0.0624
0.16, Ϫ0.21
0.0570, 0.1658
0.0749, 0.1790
0.83, Ϫ0.54
Ϫ3
˚
Largest diff. peak and hole [e·A
]
[a] One of the two CHCl3 solvate molecules per formula unit showed rather high displacement ellipsoids, and the highest residual electron
density was found in this region. The occupancy factor of this molecule was refined and finally fixed at 0.80.
1996, 338, 441Ϫ450. [3c] R. Reinhard, M. Glaser, R. Neumann,
G. Maas, J. Org. Chem. 1997, 62, 7744Ϫ7751.
G. Maas, J. Prakt. Chem. 2000, 342, 235Ϫ239.
5) ppm. 31P NMR: δ ϭ 40.8 ppm. MS (EI, 70 eV): m/z (%) ϭ 667
(50) [Mϩ], 608 (82) [Mϩ Ϫ CO2Me], 582 (97) [Mϩ Ϫ C4H7NO],
450 (62) [Mϩ Ϫ Ph2PS], 418 (100). C37H34NO5PS2·CHCl3 (787.15):
calcd. C 57.98, H 4.48, N 1.78; found C 58.37, H 4.58, N 1.89.
[3d]
J. Schlegel,
[4]
G. Maas, E.-U. Würthwein, B. Singer, T. Mayer, D. Krauss,
Chem. Ber. 1989, 122, 2311Ϫ2317.
[5] [5a]
X-ray Crystallographic Study:[30] Single crystals of 10 were obtained
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Received February 7, 2003
Eur. J. Org. Chem. 2003, 2071Ϫ2079
www.eurjoc.org
 2003 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
2079