TfOH-Catalyzed Phosphinylation of 2,3-Allenols into ?-Ketophosphine Oxides

Article abstract of DOI:10.1021/acs.joc.0c00328

The first facile and efficient acid-catalyzed direct coupling of a wide range of unprotected 2,3-allenols with arylphosphine oxides was developed, offering a general, one-step approach for the synthesis of structurally diverse ?-ketophosphine oxides accompanied by concurrent C-P/Ca?O bond formation with remarkable functional group tolerance and complete atom-economy under metal- A nd additive-free conditions. Mechanistic studies showed that this transformation involved a rearrangement and a phospha-Michael reaction.

Full text of DOI:10.1021/acs.joc.0c00328

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Note
TfOH-Catalyzed Phosphinylation of 2,3-
Allenols into #-Ketophosphine Oxides
Runmin Zhao, Xianhua Huang, Minning Wang, Shanshan Hu, Yuxing Gao, Pengxiang Xu, and Yufen Zhao
J. Org. Chem., Just Accepted Manuscript • DOI: 10.1021/acs.joc.0c00328 • Publication Date (Web): 26 May 2020
Downloaded from pubs.acs.org on May 26, 2020
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TfOH-Catalyzed Phosphinylation of 2,3-Allenols into
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γ-Ketophosphine Oxides
Runmin Zhao,† Xianhua Huang,† Minning Wang,‡ Shanshan Hu,‡ Yuxing Gao,‡* Pengxiang Xu‡* and Yufen
Zhao‡
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†Department of Chemical and Biochemical Engineering, College of Chemistry and Chemical Engineering,
Xiamen University, Xiamen 361005, Fujian, China.
‡Department of Chemistry and Key Laboratory for Chemical Biology of Fujian Province, College of
Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, Fujian, China.
*E-mail: gaoxingchem@xmu.edu.cn; xpengxiang@xmu.edu.cn.
RECEIVED DATE (will be automatically inserted after manuscript is accepted).
Table of Contents Graphic:
R4
R1
R
2 R1
O
O
TfOH (30 mol%)
HO
R2
O
R5
R6
•
R5
+
H
P
R6
P
R6
THF, 100 °C, 24 h, Ar
R6
R4 R3
R3
R1 = Ar, alkyl, alkenyl, alkynyl;
R2, R3 = H, Me; R4 = H, Ph;
R5 = H, Ph, nBu; R6 = Ar, nBu.
metal free
additive free
unprotected
41 examples
up to 99% yield
Abstract: The first facile and efficient acid-catalyzed direct coupling of a wide range of unprotected 2,3-allenols
with arylphosphine oxides was developed, offering a general, one-step approach for the synthesis of structurally
diverse γ-ketophosphine oxides accompanied by concurrent C―P/C ＝ O bond formation with remarkable
functional group tolerance and complete atom-economy under metal- and additive-free conditions. Mechanistic
studies showed that this transformation involved a rearrangement and a phospha-Michael reaction.
Organophosphorus compounds have found widespread applications in organic synthesis, medicinal chemistry,
agricultural chemistry and materials science.1 Among them, γ-ketophosphine oxides have attracted extensive
attention in organic and medicinal chemistry over the past few decades due to their unique structural features and
diverse intriguing biological properties.2 Thus, intense research interests have been paid to develop synthetic
approaches to such promising frameworks. The majority of these methods involve the conjugate addition of
phosphorus nucleophiles to α, β-unsaturated carbonyl compounds, namely the phospha-Michael reaction (Scheme
1a), which suffers from the use of a large amount of bases3 or complex N-heterocyclic carbene4 as the catalyst and
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the limited substrate scope. To address these disadvantages, a few synthetic methods have emerged in recent years.
In 2014, the Ag-promoted radical phosphinylation of α,α-diaryl allylic alcohols with arylphosphine oxides for the
preparation of γ-ketophosphine oxides was revealed, which is usually plagued by the use of a large amount of
noble Ag salts (Scheme 1b, eq 1).5 In 2017, our group established a Zn(OTf)2-catalyzed direct coupling of
propargylic alcohols with P(O)H compounds to access γ-ketophosphine oxides in the presence of Ph2P(O)OH
(Scheme 1c), but their general use poses severe limitations due to environmentally unfriendly metal catalyst and
the limited substrate scope.6 Very recently, Zhang’s group developed Eosin Y-catalyzed phosphinylation of allylic
alcohols assisted by blue LEDs (Scheme 1b, eq 2).7 Although these synthetic methods have proven to be efficient,
the development of new catalytic systems with different synthons for the synthesis of diverse γ-ketophosphine
oxides for biological screening under metal- and additive-free conditions is still of great significance.
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Scheme 1. Synthetic Strategies towards γ-Ketophosphine Oxides
(a) Phospha-Michael reaction:
O
O
P(O)R2
O
base
NHC
H
P
R
+
R1
R2
R1
R2
R
O
O
O
P(O)Ph2
+
H
P
Ph
Ph
R
Ph
R
Ph
(b) Radical phosphinylation of diaryl allyic alcohols:
Ar2
O
O
HO
AgOAc (3 equiv)
(1)
P(O)Ar2
+
H
P
Ar
Ar1 Ar2
Ar1
Ar
O
O
Ar
HO
Ar Ar
Eosin Y
(2)
+
H
P
R1
R2
blue LEDs
Ar
P(O)R1R2
(c) Zn(OTf)2-catalyzed phosphinylation of propargylic alcohols:
OH
O
O
P(O)R2
2
Zn(OTf)2
H
P
R2
R2
+
Ar
R1
Ar
Ph2P(O)OH
R1
(d) This work: TfOH-catalyzed phosphinylation of 2,3-allenols:
R4
R1 R2
O
R1
O
O
TfOH
R5
HO
R2
R5
+
H
P
R6
R6
•
P
R6
R4 R3
R6
R3
Over the past several years, 2,3-allenols and their derivatives have been employed as structurally diverse and
fascinating building blocks for the construction of C―C and C―X bonds8 as well as for the preparation of a wide
range of valuable molecular frames in modern organic synthesis, such as dihydrofurans,9 lactams,10 enynes,11
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2-pyrrolines,12 carbazoles13 and furanones.14 Inspired by these precedents and our recent work on C―P bond
formation,15 we disclosed the first example of a single-step and selective synthesis of structurally diverse
γ-ketophosphine oxide frameworks via a simple and efficient Brønsted acid-catalyzed direct phosphinylation of
unprotected 2,3-allenols under metal-free and additive-free conditions with remarkable functional group tolerance,
high regioselectivity, complete atom-economy and moderate to excellent yields (Scheme 1d). This metal-free
strategy provided a facile and rapid access to various novel γ-ketophosphine oxides, which were not easily
accessible by the known methods, along with the formation of new C―P and C＝O bonds.
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Table 1. Optimization of the Reaction Conditionsa
O
Ph
O
OH
catalyst
O
+
H
P
Ph
•
P
solvent, temp
Ph
Ph
Ph
2a
Ph
3a
1a
entry
1
catalyst
solvent
DCE
temp (°C)
yield (%)
81
Zn(OTf)2 (20)
Zn(OTf)2 (20)
Zn(OTf)2 (20)
Zn(OTf)2 (20)
Al(OTf)3 (20)
NHTf2 (20)
100
100
100
100
100
100
100
100
100
100
100
100
100
100
100
100
100
90
2
toluene
69
3
dioxane
THF
THF
THF
THF
THF
THF
THF
THF
THF
THF
THF
toluene
DCM
DCE
THF
THF
87
4
90
5
88
6
76
7
B(PhF5)3 (20)
BF3·Et2O (20)
TFAb (20)
35
8
64
9
24
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11
12
13
14
15
16
17
18
19
H2SO4 (20)
82
TfOH (20)
92
0
TfOH (30)
TfOH (40)
TfOH (10)
TfOH (10)
TfOH (10)
TfOH (30)
TfOH (30)
95
93
58
27
89
91
110
88
aReaction conditions: 1a (0.4 mmol), 2a (0.48 mmol), catalyst (mol %), and solvent (2 mL) at the indicated
temperature for 24 h under argon. bTrifluoroacetic acid.
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Our initial investigation focused on the C―P coupling reaction of 1-phenyl-2,3-butadien-1-ol 1a with
diphenylphosphine oxide 2a as summarized in Table 1. Gratifyingly, preliminary attempts using 20 mol % of
Zn(OTf)2 as the catalyst in 1,2-dichloroethane (DCE) at 100 °C for 24 h under an argon atmosphere resulted in
clean formation of anticipated product 3a in a high yield of 81% (Table 1, entry 1). Encouraged by this
promisingresult, we turned to screen the effect of other solvents such as toluene, dioxane and tetrahydrofuran
(THF), and found that THF was the optimal solvent for this reaction and could enhance the yield up to 90% (Table
1, entries 1-4). Subsequently, the performance of a series of catalysts was examined. Substituting Zn(OTf)2 for
Al(OTf)3, NHTf2, B(PhF5)3 or BF3·Et2O as Lewis acid gave rise to a decrease of the yield of 3a (entries 5-8). A
screening of various Brønsted acids including TEA, H2SO4 and TfOH as the catalyst was then carried out, with the
finding that the formation of 3a was observed in all cases and simple TfOH gave the best result for this reaction,
providing the desired product 3a in an excellent yield of 92% (entries 9-11). Conversely, no product was detected
in the absence of TfOH, and only starting materials were recovered (entry 12). To our delight, increasing the
loading of TfOH to 30 mol % could enhance the yield of 3a up to 95% (entry 13). Yet, further increasing the
TfOH loading led to a slight decrease in yield (entry 14). Considering that THF may form the complex with the
TfOH and weaken the acidity of the TfOH, we retested the effect of various solvents such as toluene, DCM and
DCE by using 10 mol % of TfOH, but none of these gave better results (entries 15-17), indicating that THF was
the optimal solvent for the reaction. Finally, the effect of temperature was evaluated, and we found that increasing
or decreasing the temperature from 100 °C resulted in the yield reduction (entries 18 and 19).
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Table 2. Substrate Scope of 2,3-Allenolsa
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8
R4
R1
R2 R1
O
O
TfOH (30 mol%)
HO
R2
O
R5
•
R5
+
H
P
Ph
P
Ph
THF, 100 °C, 24 h, Ar
Ph
Ph
R4 R3
R3
9
1
2a
3
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3f
, R = 4-F, 88%
3a
, R = H, 95%
3k
, R = 4-NO2, 94%
R
3g
, R = 4-Me, 99%
3h, R = 4-CF3, 71%
3b
3c
3d
3e
, R = 4-Cl, 97%
, R = 3-Cl, 99%
, R = 2-Cl, 94%
, R = 4-Br, 92%
3l
3m
, R = 4-CN, 74%
O
, R = 4-Ph, 98%
, R = 4-OMe, 99%
O
3i
3j
, R = 4-SMe, 50%
, R = 4-CO2Me, 91%
3n
P
Ph
Ph
N
O
O
S
O
O
O
O
O
O
O
P
Ph
P
P
P
Ph
Ph
Ph
Ph
Ph
Ph
Ph
b
3o
3p
3q
3r
, 42%
, 95%
, 73%
, 99%
S
Ph
4
O
O
O
O
O
O
P
O
O
P
Ph
P
Ph
P
Ph
, 92%
Ph
Ph
Ph
Ph
Ph
3s
3t
3u
3v
, 77%
, 91%
, 85%
Ph
Ph
O
O
O
O
Ph
5
O
O
O
O
O
P
P
Ph
P
Ph
P
Ph
Ph
Ph
Ph
Ph
Ph
, 55%
3w
3x
3y
3z
, 99%
, 86%
, 79%
O
O
Ph
Ph
O
Ph
O
O
O
Ph
Ph
O
P
P
P
Ph
P
Ph
Ph
Ph
Ph
Ph
Ph
Ph
, 89%
Ph
3ac
c
3aa
3ab
3ad
, 25%
, 87%, dr = 65:35
R
, 56%
4
O
3af
, R = H, 90%
O
O
3ag
3ah
3ai
, R = Cl, 85%
, R = Me, 88%
, R = CF3, 57%
nBu
P
O
P
Ph
Ph
Ph
, 42%
nBu
Ph
3ae
aReaction conditions: 1a (0.4 mmol), 2a (0.48 mmol), TfOH (30 mol %), and THF (2 mL) at 100 °C for 24 h under
argon. Using 130 mol % of TfOH at 90 ℃. Diastereomer ratios were determined by 31P NMR analysis of the
b
c
crude products.
With the optimized conditions in hand (footnote a, Table 2), the substrate scope of the phosphinylation of
various structurally and electronically modulated 2,3-allenols with diphenylphosphine oxide 2a was explored, and
the results are summarized in Table 2. In the beginning, 13 derivatives (1b-1n) of 1a with different
election-donating or -withdrawing groups on the phenyl ring were tested. Various substituents such as Me, Ph,
OMe, SMe, F, Cl, Br, CF3, CO2Me, NO2 and CN were all well tolerated for this method and their electronic nature
was not evident for this transformation. The bulky naphthyl-derived 2,3-allenol underwent the coupling to afford
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the desired products 3o in 95% yield. In addition, substrates incorporating heterocyclic groups such as furyl (1p),
thienyl (1q), or benzothienyl (1s) were also tolerated well. Subjecting pyridyl-substituted 2,3-allenol 1r to the
standard reaction conditions did not afford the targeted product, yet, using 1.3 equivalents of TfOH at 90 °C, the
reaction could give the expected product 3r in 42% yield. To our delight, aliphatic 2,3-allenols 1t-1v could also
successfully be applied to this coupling. Interestingly, 1w and 1x having double bond and triple bond at C1
position all worked under the standard conditions. In addition to secondary 2,3-allenols, tertiary 2,3-allenols were
also successfully engaged in this reaction, producing the corresponding products 3y-3aa in good to excellent yields
of 79-99%. It should be noted that tertiary 2,3-allenols such as 1,1-diphenyl-buta-2,3-dien-1-ol with two phenyls at
the C1 position failed to afford the expected product under the optimized conditions, which might be attributed to
steric hindrance. After investigating the reactivity of 1-substituted 2,3-allenols, we turned our attention to the use
of 1,2-disubstituted 2,3-allenols. When a methyl group was introduced at C2 position, 1ab could be converted into
the desired product 3ab in high total yield along with a diastereomeric ratio of 65:35. Next, the influence of
substituents at the terminal position of the allene moiety was surveyed. 4,4-Diphenyl-substituted 2,3-allenol 1ac
could also participate in the reaction to generate the corresponding product 3ac in 56% yield. However, when
4-phenyl-substituted 2,3-allenol 1ad was employed, an unsatisfactory yield of 25% was obtained. It is noteworthy
that 2,3-allenols with an alkyl group at their C5 position were also compatible with this protocol and gave the
relative products 3ae-3ai in moderate to good yields. Fortunately, the product 3e was recrystallized from acetone
as colorless crystals by slow evaporation at room temperature, the molecular structure of 3e was confirmed by
X-ray diffraction analysis (see the Supporting Information for detailed X-ray crystallography data).16 The result
clearly showed the phosphoryl moiety was preferentially installed at C1-position of 2,3-allenols in the present
coupling reaction.
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Table 3. Substrate Scope of P(O)H Compoundsa
5
6
7
8
O
P
R2
O
OH
TfOH (30 mol%)
+
H
P
R2
R3
•
R3
THF, 100 °C, 24 h, Ar
Ph
O
Ph
1a
2
3
: R , R = pMePh; : R , R = pClPh; : R , R3 = pMeOPh;
9
2
3
2
3
2
2b
2e
2c
2d
: R , R = nBu; : R2 = Ph, R3 = OEt; : R , R = OEt; : R2 = Ph, R3 = tBu
2
3
2
3
2f
2g
2h
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11
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O
P
O
P
O
P
O
P
Ph-CH3-p
Ph-CH3-p
Ph-Cl-p
Ph-Cl-p
Ph-OCH3-p
Ph-OCH3-p
nBu
nBu
O
Ph
O
Ph
O
Ph
O
Ph
b
3aj
3ak
3al
3am
, 67%
, 99%
, 95%
, 94%
O
O
P
O
P
Ph
P
OEt
OEt
OEt
Ph
O
Ph
O
Ph
O
Ph
c
d
3an
3ao
3ap
, 81%, dr = 3.4:1
, 12%, dr = 1.6:1
, 0%
aReaction conditions: 1a (0.4 mmol), 2a (0.48 mmol), TfOH (30 mol %), and THF (2 mL) at 100 °C for 24 h under
argon. bAt 140 °C. cIn EtOAc. dDiastereomer ratio was determined by 1H NMR analysis of the mixture.
To gain more insight into the versatility of the reaction, some other P(O)H substrates were also evaluated. As
shown in Table 3, apart from 2a, other diarylphosphine oxides such as 2b, 2c and 2d were all suitable reaction
partners, and afforded the desired products 3aj-3al in excellent yields (94%-99%). Moreover, dibutylphosphine
oxide 2e could also be successfully converted into the corresponding product 3am in 67% yield by increasing the
temperature to 140 °C. Nevertheless, ethyl phenylphosphinate 2f only provided the target product 3an in a lower
yield of 12%. Notably, H-phosphonates like diethyl phosphonate was almost inert in the present catalytic system,
probably due to the electronic properties of P(O)H compounds. To examine the stereochemistry of this reaction,
optically pure (S)-tert-butyl(phenyl)phosphine oxide (99% ee) 2h was used as the substrate under the standard
reaction conditions, but the corresponding product 3ap was acquired in a racemic form，which was proposed with
the low diastereocontrol (3.4:1 dr).
Scheme 2. Application Studies
O
Ph
O
OH
TfOH (30 mol%)
O
+
H
P
Ph
(a)
(b)
•
P
THF, 100 °C, 24 h, Ar
Ph
1a
Ph
Ph
Ph
, 3.46 g, 99% yield
2a
3a
, 1.46 g
Ph
, 2.43 g
O
Ph
O
O
O
HBr (3 equiv)
P
Ph
P
Ph
Ph
DMSO, 55 °C, 4 h
Ph
Br
4
, 56% yield
1a
, 1.0 mmol
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To demonstrate the practical utility of this method, a gram-scale reaction of 1a (1.46 g, 10 mmol) with 2a (2.43
g, 12 mmol) was conducted to afford the expected product 3a (3.46 g) in 99% yield (Scheme 2a), indicating that
the reaction could be effectively scaled up without decreasing the yields. Moreover, the products could be easily
transformed to other derivatives. 5,17 For example, 3a could react with HBr to produce a useful α-bromocarbonyl
compound 4 (Scheme 2b).
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Scheme 3. Mechanistic Studies
OH
O
TfOH
(a)
(b)
•
TfOH (30 mol%): 51% yield
TfOH (0 mol%): 0% yield
Ph
1a
Ph
THF (5 mL)
100 °C, 24 h, Ar
5
, 1.0 mmol
O
O
Ph
O
O
TfOH (30 mol %)
+
H
P
Ph
P
Ph
THF (2 mL)
Ph
Ph
Ph
, 96% yield
100 °C, 24 h, Ar
5,
2a
3a
0.4 mmol
, 0.48 mmol
To gain preliminary insight into the reaction mechanism, several control experiments were performed (Scheme
3). Treatment of 1a under the standard reaction conditions without 2a, as expected, enone 5 was obtained in 51%
yield. Yet, no product 5 was observed in the absence of TfOH (Scheme 3a). Further treatment of enone 5 with 2a
could give the targeted product 3a in 96% yield (Scheme 3b), showing that enone 5 should be the key intermediate
in this transformation.
Scheme 4. Plausible Mechanism
R4
R4
R4
R2 OH
R2
R1 R2
R2
H2O
H
R4
•
R5
R5
O
•
R5
O
R1
-
R1
R1
HO
-
H2O
H
R3 R5
R3
R3
R3
B
1
A
C
H
O
R2
O
Ph2P
OH
Ph2P
R1
R4
R4
R1
R4
R1
-H+
R2
R2
R3 R5
R3 R5
R3 R5
D
E
3
H
O
H PPh2
O
PPh2
2a'
2a
On the basis of the experimental results and related literature reports,18-20 we proposed a tentative mechanism for
this transformation (Scheme 4). Initially, the elimination of the hydroxyl group in the 2,3-allenol moiety easily
occurred with the aid of TfOH to produce the carbenium ion A, followed by electron transfer of A to afford the
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corresponding vinyl cation B.18b Ensuing nucleophilic attack of water led to an enol intermediate C, which
immediately isomerizes to form the key enone intermediate D.18 Finally, the intermolecular phospha-Michael
addition of the phosphorus nucleophile 2' (tautomerized from 219) to D resulted in the formation of an enol
intermediate E with the assistance of TfOH,20 followed by enol-keto tautomerism of E to generate the desired
product 3.
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In conclusion, we have developed the first facile and efficient TfOH-catalyzed direct phosphinylation of a wide
range of 2,3-allenols with H-phosphine oxides, affording a rapid and powerful tool to a structurally diverse array
of γ-ketophosphine oxides along with concurrent new C＝O and C―P bonds formation. Importantly, the present
method avoids metals and other additives, and various valuable γ-ketophosphine oxide moieties could be easily
obtained through a simple one-step process. Mechanistic investigations showed that this transformation involved a
rearrangement to the enone intermediate, followed by the phospha-Michael reaction. In addition, the use of readily
available TfOH as the catalyst, operational simplicity, remarkable functional group tolerance, excellent
regioselectivity and complete atom economy mean that this method will open a new avenue to potential biological
active γ-ketophosphine oxide and find widespread applications in synthetic chemistry and medicinal chemistry.
EXPERIMENTAL SECTION
General Information
Unless otherwise stated, all reactions were carried out under dry argon. 1a-1aa,21 1ab,12 1ac, 221ad,23 1ae-1ai,24
2c-2d,25 2e,26 2h,27 substrates were prepared according to the known reference. Other reagents were obtained from
commercial suppliers and used without further purification. All the heating experiments were performed in an oil
bath. 1H, 13C and 31P NMR spectra were recorded on a Bruker AV500 spectrometer using tetramethylsilane (TMS)
in CDCl3 as the internal standard. NMR chemical shifts were determined relative to CDCl3 as the internal
reference (δH = 7.26 ppm, δC = 77.16 ppm). NMR data are represented as follows: chemical shift, multiplicity (s =
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singlet, d = doublet, t = triplet, q = quartet, m = multiplet), coupling constants in Hertz (Hz), integration. HRMS
spectra of all products were recorded on a Waters Micromass LCT Premier TOF-MS apparatus. Infrared spectra
were recorded on a Nicollet Avatar 330 spectrometer. Melting points were recorded on a MP120 Digital
Melting-Point apparatus. The products were purified by column chromatography on silica gel 300-400 mesh. Flash
column chromatography purification was carried out by a gradient elution method using ethyl acetate (EA) in light
petroleum ether (PE).
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General Procedure for the Synthesis of γ-Ketophosphine Oxides (3aa-3ap). To a Schlenk tube equipped with a
magnetic stir bar were added 2,3-allenols (0.4 mmol), H-phosphine oxides (0.48 mmol), and TfOH (0.12 mmol) in
THF (2 mL) under argon, and the mixture was kept stirring at 100 °C in an oil bath for 24 h. The resulting mixture
was cooled down to room temperature and purified by flash chromatography (petroleum ether/ethyl acetate) to
afford the corresponding products.
1
4-(Diphenylphosphinyl)-4-phenylbutan-2-one (3a).28 95% yield, 132 mg; white solid; mp 185.1−187.7 °C; H
NMR (CDCl3, 500 MHz): δ 7.95−7.92 (m, 2H), 7.57−7.50 (m, 3H), 7.46−7.43 (m, 2H), 7.33−7.28 (m, 3H),
7.24−7.20 (m, 2H), 7.17−7.10 (m, 3H), 4.23 (ddd, J = 10.0, 7.3, 2.7 Hz, 1H), 3.33 (ddd, J = 17.6, 10.1, 5.4 Hz, 1H),
2.95 (ddd, J = 17.8, 11.2, 2.6 Hz, 1H), 1.94 (s, 3H); 13C{1H} NMR (CDCl3, 125 MHz): δ 205.3 (d, JC−P = 12.6 Hz),
135.8 (d, JC−P = 5.4 Hz), 132.0 (d, JC−P = 2.7 Hz), 131.8 (d, JC−P = 7.3 Hz), 131.4 (d, JC−P = 2.7 Hz), 131.3 (d, JC−P
= 8.2 Hz), 131.0 (d, JC−P = 9.1 Hz), 129.3 (d, JC−P = 103.5 Hz), 129.2 (d, JC−P = 109.9 Hz), 128.3 (d, JC−P = 1.8 Hz),
128.1, 128.0, 127.1 (d, JC−P = 2.7 Hz), 43.5, 41.1 (d, JC−P = 68.3 Hz), 30.6; 31P{1H} NMR (CDCl3, 202 MHz): δ
33.6; IR (film) υmax 2918, 1715, 1202, 1108 cm−1; HRMS (ESI-TOF) m/z [M + H]+ calcd for C22H21O2PH+
349.1352, found 349.1352.
4-(Diphenylphosphinyl)-4-(4-chlorophenyl)butan-2-one (3b).29 97% yield, 149 mg; white solid; mp 215.5−216.5
°C; 1H NMR (CDCl3, 500 MHz): δ 7.85−7.82 (m, 2H), 7.48−7.37 (m, 5H), 7.27−7.24 (m, 1H), 7.19−7.15 (m, 4H),
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7.05−7.03 (m, 2H), 4.13 (ddd, J = 10.0, 7.3, 2.6 Hz, 1H), 3.18 (ddd, J = 18.0, 10.2, 5.1 Hz, 1H), 2.84 (ddd, J =
18.1, 11.0, 2.6 Hz, 1H), 1.86 (s, 3H); 13C{1H} NMR (CDCl3, 125 MHz): δ 204.9 (d, JC−P = 12.6 Hz), 134.6 (d, JC−P
= 5.5 Hz), 133.0 (d, JC−P = 2.8Hz), 132.1 (d, JC−P = 2.7 Hz), 131.6 (d, JC−P = 2.8Hz), 131.5, 131.2(d, JC−P = 8.7 Hz),
131.0 (d, JC−P = 5.6 Hz), 130.8 (d, JC−P = 8.6 Hz), 130.7, 128.6 (d, JC−P = 89.2 Hz), 128.6 (d, JC−P = 89.8 Hz), 128.5
(d, JC−P = 1.6 Hz), 43.5, 40.1 (d, JC−P = 68.3 Hz), 30.5; 31P{1H} NMR (CDCl3, 202 MHz): δ 33.2; IR (film) υmax
3053, 2921, 1715, 1176, 1119 cm−1; HRMS (ESI-TOF) m/z [M + H]+ calcd for C22H20ClO2PH+ 383.0962, found
383.0962.
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4-(Diphenylphosphinyl)-4-(3-chlorophenyl)butan-2-one (3c). 99% yield, 152 mg; white solid; mp 196.4−198.3
°C; 1H NMR (CDCl3, 500 MHz): δ 7.86−7.82 (m, 2H), 7.50−7.43 (m, 3H), 7.40−7.37 (m, 2H), 7.28−7.25 (m, 1H),
7.21−7.17 (m, 3H), 7.14−7.11 (m, 1H), 7.01−6.98 (m, 2H), 4.13 (ddd, J = 10.1, 7.4, 2.8 Hz, 1H), 3.20 (ddd, J =
18.1, 10.1, 5.3 Hz, 1H), 2.86 (ddd, J = 18.1, 11.2, 2.4 Hz, 1H), 1.88 (s, 3H); 13C{1H} NMR (CDCl3, 125 MHz): δ
204.8 (d, JC−P = 12.5 Hz), 138.1 (d, JC−P = 5.4 Hz), 134.0 (d, JC−P = 1.8 Hz), 132.2 (d, JC−P = 2.7 Hz), 131.7 (d, JC−P
= 2.7 Hz), 131.2 (d, JC−P = 9.0 Hz), 130.9 (d, JC−P = 8.2 Hz), 129.8 (d, JC−P = 6.4 Hz), 129.5 (d, JC−P = 1.7 Hz),
128.6 (d, JC−P = 94.5 Hz), 128.5 (d, JC−P = 93.7 Hz), 127.8 (d, JC−P = 5.2 Hz), 127.3 (d, JC−P = 2.0 Hz), 43.4, 40.5
(d, JC−P = 67.7 Hz), 30.5; 31P{1H} NMR (CDCl3, 202 MHz): δ 33.2; IR (film) υmax 3056, 2923, 1720, 1179, 1119
cm−1; HRMS (ESI-TOF) m/z [M + H]+ calcd for C22H20ClO2PH+ 383.0962, found 383.0965.
4-(Diphenylphosphinyl)-4-(2-chlorophenyl)butan-2-one (3d). 94% yield, 144 mg; white solid; mp 159.9−161.0
°C; 1H NMR (CDCl3, 500 MHz): δ 7.94−7.90 (m, 2H), 7.70−7.68 (m, 1H), 7.53−7.47 (m, 3H), 7.35−7.31 (m, 2H),
7.25−7.22 (m, 1H), 7.17−7.14 (m, 1H), 7.13−7.09 (m, 2H), 7.04−6.97 (m, 2H), 4.82 (ddd, J = 10.2, 7.1, 3.3 Hz,
1H), 3.26 (ddd, J = 17.4, 10.2, 6.4 Hz, 1H), 2.90 (ddd, J = 17.9, 10.2, 3.2 Hz, 1H), 1.87 (s, 3H); 13C{1H} NMR
(CDCl3, 125 MHz): δ 204.6 (d, JC−P = 12.3 Hz), 134.8 (d, JC−P = 7.4 Hz), 134.1 (d, JC−P = 4.7 Hz), 132.2 (d, JC−P
=
2.7 Hz), 131.6 (d, JC−P = 3.0 Hz), 131.4 (d, JC−P = 8.5 Hz), 130.9 (d, JC−P = 9.8 Hz), 129.9 (d, JC−P = 4.5 Hz), 129.3
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(d, JC−P = 1.5 Hz), 128.5 (d, JC−P = 137.4 Hz), 128.4 (d, JC−P = 93.7 Hz), 128.3 (d, JC−P = 2.4 Hz), 127.1 (d, JC−P =
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2.0 Hz), 43.7, 36.4 (d, JC−P = 67.3 Hz), 30.2; 31P{1H} NMR (CDCl3, 202 MHz): δ 33.7; IR (film) υmax 3057, 2929,
1715, 1187, 1117 cm−1; HRMS (ESI-TOF) m/z [M + H]+ calcd for C22H20ClO2PH+ 383.0962, found 383.0962.
4-(Diphenylphosphinyl)-4-(4-bromophenyl)butan-2-one (3e).30 92% yield, 157 mg; white solid; mp 225.7−226.6
°C; 1H NMR (CDCl3, 500 MHz): δ 7.93−7.89 (m, 2H), 7.58−7.51 (m, 3H), 7.49−7.45 (m, 2H), 7.38−7.35 (m, 1H),
7.30−7.25 (m, 4H), 7.20−7.18 (m, 2H), 4.19 (ddd, J = 10.0, 7.2, 2.7 Hz, 1H), 3.27 (ddd, J = 18.1, 10.2, 5.1 Hz, 1H),
2.92 (ddd, J = 18.1, 11.0, 2.7 Hz, 1H), 1.96 (s, 3H); 13C{1H} NMR (CDCl3, 125 MHz): δ 204.9 (d, JC−P = 12.6 Hz),
135.1 (d, JC−P = 5.5 Hz), 132.1 (d, JC−P = 12.7 Hz), 131.7 (d, JC−P = 2.7 Hz), 131.6 (d, JC−P = 9.4 Hz), 131.4 (d, JC−P
= 1.7 Hz), 131.4 (d, JC−P = 5.3 Hz), 131.2 (d, JC−P = 8.8 Hz), 130.9 (d, JC−P = 8.8 Hz), 130.8 (d, JC−P = 4.6 Hz),
128.7 (d, JC−P = 87.4 Hz), 128.6 (d, JC−P = 87.7 Hz), 121.2 (d, JC−P = 3.2 Hz), 43.5, 40.2 (d, JC−P = 67.9 Hz), 30.5;
31P{1H} NMR (CDCl3, 202 MHz): δ 33.0; IR (film) υmax 3050, 2918, 1713, 1175, 1119 cm−1; HRMS (ESI-TOF)
m/z [M + H]+ calcd for C22H20BrO2PH+ 427.0457, found 427.0457.
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4-(Diphenylphosphinyl)-4-(4-fluorophenyl)butan-2-one (3f).31 88% yield, 129 mg; white solid; mp 177.4−178.8
°C; 1H NMR (CDCl3, 500 MHz): δ 7.94−7.91 (m, 2H), 7.58−7.51 (m, 3H), 7.47−7.43 (m, 2H), 7.36−7.33 (m, 1H),
7.30−7.24 (m, 4H), 6.87−6.84 (m, 2H), 4.21 (ddd, J = 1 Hz, 1H), 3.28 (ddd, J = 17.8, 10.2, 5.1 Hz, 1H), 2.92 (ddd,
J = 18.0, 10.9, 2.4 Hz, 1H), 1.96 (s, 3H); 13C{1H} NMR (CDCl3, 125 MHz): δ 205.1 (d, JC−P = 12.8 Hz), 161.9 (d,
JC−F = 246.1 Hz), 132.1 (d, JC−P = 2.8 Hz), 131.8, 131.5 (d, JC−P = 2.8 Hz), 131.3 (d, JC−P = 5.4 Hz), 131.2 (d, JC−P
= 8.8 Hz), 131.2 (d, JC−P = 5.4 Hz), 130.9 (d, JC−P = 9.1 Hz), 128.6 (d, JC−P = 95.2 Hz), 128.5 (d, JC−P = 95.4 Hz),
115.4 (d, JC−P = 1.8 Hz), 115.2 (d, JC−P = 1.8 Hz), 43.7, 40.0 (d, JC−P = 68.6 Hz), 30.6; 31P{1H} NMR (CDCl3, 202
MHz): δ 33.4; IR (film) υmax 3056, 2921, 1715, 1175, 1117 cm−1; HRMS (ESI-TOF) m/z [M + H]+ calcd for
C22H20FO2PH+ 367.1258, found 367.1257.
1
4-(Diphenylphosphinyl)-4-(4-tolyl)butan-2-one (3g).31 99% yield, 144 mg; white solid; mp 195.6−198.3 °C; H
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NMR (CDCl3, 500 MHz): δ 7.93−7.90 (m, 2H), 7.56−7.44 (m, 5H), 7.35−7.32 (m, 1H), 7.26−7.22 (m, 2H),
7.18−7.16 (m, 2H), 6.97−6.95 (m, 2H), 4.19 (ddd, J = 10.2, 7.6, 2.8 Hz, 1H), 3.29 (ddd, J = 17.5, 10.2, 5.4 Hz, 1H),
2.92 (ddd, J = 17.7, 11.1, 2.5 Hz, 1H), 2.22 (s, 3H), 1.94 (s, 3H); 13C{1H} NMR (CDCl3, 125 MHz): δ 205.4 (d,
JC−P = 12.5 Hz), 136.7 (d, JC−P = 2.7 Hz), 132.6 (d, JC−P = 5.4 Hz), 132.0 (d, JC−P = 4.1 Hz), 131.9 (d, JC−P = 2.6
Hz), 131.4 (d, JC−P = 2.7 Hz), 131.3 (d, JC−P = 8.4 Hz), 131.3 (d, JC−P = 10.0 Hz), 131.0 (d, JC−P = 8.3 Hz), 129.6 (d,
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JC−P = 5.6 Hz), 129.1 (d, JC−P = 1.5 Hz), 128.5 (d, JC−P = 97.0 Hz), 128.4 (d, JC−P = 98.0 Hz), 43.6, 40.4 (d, JC−P
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68.7 Hz), 30.6, 21.0; 31P{1H} NMR (CDCl3, 202 MHz): δ 33.4; IR (film) υmax 3056, 2921, 1709, 1174, 1120 cm−1;
HRMS (ESI-TOF) m/z [M + H]+ calcd for C23H23O2PH+ 363.1508, found 363.1508.
4-(Diphenylphosphinyl)-4-(4-(trifluoromethyl)phenyl)butan-2-one (3h). 71% yield, 118 mg; white solid; mp
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243.9−245.7 °C; H NMR (CDCl3, 500 MHz): δ 7.95−7.91 (m, 2H), 7.60−7.52 (m, 3H), 7.48−7.40 (m, 6H),
7.37−7.34 (m, 1H), 7.27−7.24 (m, 2H), 4.29 (ddd, J = 10.0, 7.1, 2.8 Hz, 1H), 3.32 (ddd, J = 18.3, 10.2, 5.0 Hz, 1H),
2.97 (ddd, J = 18.3, 11.2, 2.8 Hz, 1H), 1.97 (s, 3H); 13C{1H} NMR (CDCl3, 125 MHz): δ 204.7 (d, JC−P = 12.2 Hz),
140.4−140.3 (m), 132.2 (d, JC−P = 2.5 Hz), 131.7 (d, JC−P = 2.6 Hz), 131.4 (d, JC−P = 15.9 Hz), 131.2 (d, JC−P = 8.8
Hz), 130.8 (d, JC−P = 9.0 Hz), 130.6 (d, JC−P = 11.6 Hz), 130.3 (d, JC−P = 5.5 Hz), 129.2, 128.7 (d, JC−P = 93.0 Hz),
128.6 (d, JC−P = 93.6 Hz), 126.3 (q, JC−F = 272.5 Hz), 125.2 (q, JC−F = 1.9 Hz), 43.5, 40.7 (d, JC−P = 67.1 Hz), 30.4;
31P{1H} NMR (CDCl3, 202 MHz): δ 33.0; IR (film) υmax 3050, 2916, 1714, 1176, 1111 cm−1; HRMS (ESI-TOF)
m/z [M + H]+ calcd for C23H20F3O2PH+ 417.1226, found 417.1229.
4-(Diphenylphosphinyl)-4-(4-methylthiophenyl)butan-2-one (3i). 50% yield, 79 mg; white solid; mp
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220.2−220.6 °C; H NMR (CDCl3, 500 MHz): δ 7.93−7. 90 (m, 2H), 7.58−7.51 (m, 3H), 7.49−7.45 (m, 2H),
7.37−7.34 (m, 1H), 7.28−7.21 (m, 4H), 7.05−7.04 (m, 2H), 4.17−4.20 (m, 1H), 3.28 (ddd, J = 17.6, 10.2, 5.2 Hz,
1H), 2.92 (ddd, J = 17.7, 11.0, 2.1 Hz, 1H), 2.40 (s, 3H), 1.95 (s, 3H); 13C{1H} NMR (CDCl3, 125 MHz): δ 205.2
(d, JC−P = 12.5 Hz), 137.3, 132.5 (d, JC−P = 5.1 Hz), 132.1, 131.7, 131.6, 131.3 (d, JC−P = 8.1 Hz), 131.0 (d, JC−P
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8.4 Hz), 130.1 (d, JC−P = 5.1 Hz), 128.6 (d, JC−P = 90.9 Hz), 128.5 (d, JC−P = 91.2 Hz), 126.4, 43.6, 40.3 (d, JC−P =
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70.2 Hz), 30.6, 15.7; 31P{1H} NMR (CDCl3, 202 MHz): δ 33.3; IR (film) υmax 2922, 1714, 1172, 1118 cm−1;
HRMS (ESI-TOF) m/z [M + H]+ calcd for C23H23O2PSH+ 395.1229, found 395.1229.
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Methyl 4-(1-(Diphenylphosphinyl)-3-oxo-3-methylpropyl)benzoate (3j). 91% yield, 147 mg; yellow solid; mp
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203.2−206.1 °C; H NMR (CDCl3, 500 MHz): δ 7.96−7.92 (m, 2H), 7.84−7.83 (m, 2H), 7.58−7.52 (m, 3H),
7.48−7.45 (m, 2H), 7.40−7.39 (m, 2H), 7.34−7.30 (m, 1H), 7.25−7.23 (m, 2H), 4.32−4.28 (m, 1H), 3.85 (s, 3H),
3.34 (ddd, J = 17.5, 10.0, 5.1 Hz, 1H), 3.00−2.95 (m, 1H), 1.95 (s, 3H); 13C{1H} NMR (CDCl3, 125 MHz): δ 204.8
(d, JC−P = 12.5 Hz), 166.8, 141.5 (d, JC−P = 5.3 Hz), 132.2 (d, JC−P = 1.8 Hz), 131.7 (d, JC−P = 2.7 Hz), 131.5 (d,
JC−P = 3.5 Hz), 131.2 (d, JC−P = 9.0 Hz), 130.8 (d, JC−P = 9.1 Hz), 130.7, 129.7 (d, JC−P = 5.6 Hz), 129.5, 128.9 (d,
JC−P = 2.1 Hz), 128.6 (d, JC−P = 93.8 Hz), 128.5 (d, JC−P = 94.5 Hz), 52.0, 43.4, 41.0 (d, JC−P = 67.0 Hz), 30.5;
31P{1H} NMR (CDCl3, 202 MHz): δ 32.9; IR (film) υmax 3056, 2917, 1719, 1182, 1116 cm−1; HRMS (ESI-TOF)
m/z [M + H]+ calcd for C24H23O4PH+ 407.1407, found 407.1406.
4-(Diphenylphosphinyl)-4-(4-nitrophenyl)butan-2-one (3k).31 94% yield, 148 mg; pale yellow solid; mp
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247.7−249.9 °C; H NMR (CDCl3, 500 MHz): δ 8.02−8.00 (m, 2H), 7.97−7.93 (m, 2H), 7.60−7.48 (m, 7H),
7.38−7.35 (m, 1H), 7.30−7.26 (m, 2H), 4.36 (ddd, J = 9.7, 6.9, 2.4 Hz, 1H), 3.35. (ddd, J = 18.4, 10.2, 5.0 Hz, 1H),
3.01 (ddd, J = 18.5, 10.9, 2.5 Hz, 1H), 1.99 (s, 3H); 13C{1H} NMR (CDCl3, 125 MHz): δ 204.4 (d, JC−P = 12.1 Hz),
146.9 (d, JC−P = 2.1 Hz), 144.1 (d, JC−P = 15.4 Hz), 132.4 (d, JC−P = 2.7 Hz), 131.9 (d, JC−P = 2.5 Hz), 131.1 (d, JC−P
= 8.5 Hz), 131.0, 130.7 (d, JC−P = 9.0 Hz), 130.6 (d, JC−P = 5.4 Hz), 130.3 (d, JC−P = 21.4 Hz), 128.8 (d, JC−P = 87.1
Hz), 128.7 (d, JC−P = 86.2 Hz), 123.4, 43.4, 40.9 (d, JC−P = 66.1 Hz), 30.3; 31P{1H} NMR (CDCl3, 202 MHz): δ
32.7; IR (film) υmax 3060, 2918, 1714, 1177, 1111 cm−1; HRMS (ESI-TOF) m/z [M + H]+ calcd for C22H20NO4PH+
394.1203, found 394.1215.
4-(1-(Diphenylphosphinyl)-3-oxo-3-methylpropyl)benzonitrile (3l). 74% yield, 116 mg; white solid; mp
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193.4−194.4 °C; H NMR (CDCl3, 500 MHz): δ 7.87−7.83 (m, 2H), 7.49−7.44 (m, 3H), 7.41−7.5 (m, 6H),
7.29−7.26 (m, 1H), 7.20−7.16 (m, 2H), 4.21 (ddd, J = 9.8, 7.1, 2.5 Hz, 1H), 3.24 (ddd, J = 18.3, 10.2, 5.0 Hz, 1H),
2.90 (ddd, J = 18.3, 10.9, 2.4 Hz, 1H), 1.89 (s, 3H); 13C{1H} NMR (CDCl3, 125 MHz): δ 204.5 (d, JC−P = 12.2 Hz),
141.9 (d, JC−P = 5.4 Hz), 132.4 (d, JC−P = 1.8 Hz), 131.9, 131.9 (d, JC−P = 2.4 Hz), 131.1 (d, JC−P = 8.6 Hz), 131.1
(d, JC−P = 29.5 Hz), 130.7 (d, JC−P = 9.1 Hz), 130.5 (d, JC−P = 5.5 Hz), 130.2, 128.8 (d, JC−P = 89.0 Hz), 128.7 (d,
JC−P = 89.6 Hz), 118.6, 110.9 (d, JC−P = 2.3 Hz), 43.3, 41.0 (d, JC−P = 66.3 Hz), 30.3; 31P{1H} NMR (CDCl3, 202
MHz): δ 32.8; IR (film) υmax 3056, 2919, 1715, 1184, 1117 cm−1; HRMS (ESI-TOF) m/z [M + H]+ calcd for
C23H20NO2PH+ 374.1304, found 374.1297.
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4-(Diphenylphosphinyl)-4-([1,1'-biphenyl]-4-yl)butan-2-one (3m). 98% yield, 166 mg; white solid; mp
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215.1−217.2 °C; H NMR (CDCl3, 500 MHz): δ 7.96−7.92 (m, 2H), 7.57−7.47 (m, 7H), 7.40−7.35 (m, 6H),
7.32−7.28 (m, 2H), 7.25−7.22 (m, 2H), 4.31−4.28 (m,1H), 3.36 (ddd, J = 16.6, 10.0, 5.2 Hz, 1H), 2.98 (ddd, J =
17.7, 11.1, 2.1 Hz, 1H), 1.97 (s, 3H); 13C{1H} NMR (CDCl3, 125 MHz): δ 205.4 (d, JC−P = 12.6 Hz), 140.5, 139.8
(d, JC−P = 1.6 Hz), 134.9 (d, JC−P = 5.4 Hz), 132.1 (d, JC−P = 1.8 Hz), 131.7 (d, JC−P = 2.6 Hz), 131.6 (d, JC−P = 2.4
Hz), 131.3 (d, JC−P = 8.1 Hz), 131.1 (d, JC−P = 8.6 Hz), 130.9, 130.1 (d, JC−P = 5.4 Hz), 128.9 (d, JC−P = 11.1Hz),
128.7, 128.2 (d, JC−P = Hz), 127.3, 127.0, 126.9, 43.5, 40.5 (d, JC−P = 67.8 Hz), 30.6; 31P{1H} NMR (CDCl3, 202
MHz): δ 33.9; IR (film) υmax 2924, 1715, 1165, 1116 cm−1; HRMS (ESI-TOF) m/z [M + H]+ calcd for
C28H25O2PH+ 425.1665, found 425.1662.
4-(Diphenylphosphinyl)-4-(4-methoxyphenyl)butan-2-one (3n).30 99% yield, 150 mg; white solid; mp
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205.1−205.8 °C; H NMR (CDCl3, 500 MHz): δ 7.84−7.80 (m, 2H), 7.43−7.36 (m, 5H), 7.22−7.19 (m, 1H),
7.14−7.10 (m, 4H), 7.59−7.58 (m, 2H), 4.10 (ddd, J = 10.1, 7.5, 2.7 Hz, 1H), 3.56 (s, 3H), 3.18 (ddd, J = 17.5, 10.2,
5.4 Hz, 1H), 2.81 (ddd, J = 17.7, 10.9, 2.6 Hz, 1H), 1.81 (s, 3H); 13C{1H} NMR (CDCl3, 125 MHz): δ 205.5 (d,
JC−P = 13.0 Hz), 158.6 (d, JC−P = 2.3 Hz), 131.9 (d, JC−P = 2.4 Hz), 131.8, 131.4 (d, JC−P = 2.4 Hz), 131.2 (d, JC−P
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8.5 Hz), 131.1, 131.0 (d, JC−P = 8.6 Hz), 130.7 (d, JC−P = 5.6 Hz), 128.5 (d, JC−P = 91.9 Hz), 128.4 (d, JC−P = 92.5
Hz), 127.6 (d, JC−P = 5.5 Hz), 113.8, 55.1, 43.6, 39.9 (d, JC−P = 69.1 Hz), 30.6; 31P{1H} NMR (CDCl3, 202 MHz):
δ 33.8; IR (film) υmax 3054, 2919, 1705, 1186, 1119 cm−1; HRMS (ESI-TOF) m/z [M + H]+ calcd for C23H23O3PH+
379.1458, found 379.1459.
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4-(Diphenylphosphinyl)-4-(naphthalen-1-yl)butan-2-one (3o). 95% yield, 151 mg; white solid; mp 212.1−212.5
°C; 1H NMR (CDCl3, 500 MHz): δ 8.12−8.11 (m, 1H), 8.04−7.99 (m, 3H), 7.69−7.64 (m, 2H), 7.56−7.53 (m, 3H),
7.44−7.27 (m, 5H), 7.06−7.04 (m, 1H), 6.94−6.91 (m, 2H), 5.23−5.19 (m, 1H), 3.43−3.37 (m, 1H), 3.23 (ddd, J =
17.6, 12.0, 3.0 Hz, 1H), 1.89 (s, 3H); 13C{1H} NMR (CDCl3, 125 MHz): δ 205.3 (d, JC−P = 11.3 Hz), 133.6, 133.0
(d, JC−P = 4.8 Hz), 132.1 (d, JC−P = 1.8 Hz), 132.0 (d, JC−P = 4.5 Hz), 131.8, 131.5 (d, JC−P = 9.0 Hz), 131.2 (d, JC−P
= 2.9 Hz), 131.0, 130.6 (d, JC−P = 9.1 Hz), 128.3 (d, JC−P = 147.2 Hz), 128.2 (d, JC−P = 147.9 Hz), 128.6, 127.8 (d,
JC−P = 1.5 Hz), 127.1 (d, JC−P = 5.4 Hz), 126.0, 125.4 (d, JC−P = 1.8 Hz), 125.3, 123.0, 44.8, 40.0 (d, JC−P = 68.5
Hz), 30.3; 31P{1H} NMR (CDCl3, 202 MHz): δ 33.9; IR (film) υmax 3054, 2924, 1715, 1187, 1115 cm−1; HRMS
(ESI-TOF) m/z [M + H]+ calcd for C26H23O2PH+ 399.1508, found 399.1506.
4-(Diphenylphosphinyl)-4-(furan-2-yl)butan-2-one (3p).29 73% yield, 99 mg; yellow solid; mp 186.9−189.9 °C;
1H NMR (CDCl3, 500 MHz): δ 7.86−7.82 (m, 2H), 7.56−7.52 (m, 3H), 7.50−7.42 (m, 3H), 7.36−7.33 (m, 2H),
7.17−7.16 (m, 1H), 6.17−6.16 (m, 1H), 6.01−6.00 (m, 1H), 4.51 (ddd, J = 10.7, 10.7, 3.1 Hz, 1H), 3.25 (ddd, J =
17.8, 10.5, 5.6 Hz, 1H), 3.00 (ddd, J = 18.0, 10.0, 3.0 Hz, 1H), 2.04 (s, 3H); 13C{1H} NMR (CDCl3, 125 MHz): δ
204.8 (d, JC−P = 11.8 Hz), 148.8 (d, JC−P = 6.4 Hz), 141.8 (d, JC−P = 2.7 Hz), 132.1 (d, JC−P = 1.8 Hz), 131.9 (d, JC−P
= 2.8 Hz), 131.4 (d, JC−P = 2.6 Hz), 131.3 (d, JC−P = 9.4 Hz), 130.8 (d, JC−P = 1.9 Hz), 130.6 (d, JC−P = 2.4 Hz),
128.5 (d, JC−P = 69.9 Hz), 128.4 (d, JC−P = 69.9 Hz), 110.7 (d, JC−P = 2.7 Hz), 108.7 (d, JC−P = 6.2 Hz), 40.8, 35.5
(d, JC−P = 69.7 Hz), 30.1; 31P{1H} NMR (CDCl3, 202 MHz): δ 32.2; IR (film) υmax 3053, 2920, 1716, 1185, 1117
cm−1; HRMS (ESI-TOF) m/z [M + H]+ calcd for C20H19O3PH+ 339.1145, found 339.1145.
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4-(Diphenylphosphinyl)-4-(thiophen-2-yl)butan-2-one (3q). 99% yield, 140 mg; white solid; mp 163.1−164.5 °C;
1H NMR (CDCl3, 500 MHz): δ 7.93−7.89 (m, 2H), 7.56−7.49 (m, 5H), 7.40−7.37 (m, 1H), 7.31−7.28 (m, 2H),
7.06−7.05 (m, 1H), 6.93−6.92 (m, 1H), 6.80−6.79 (m, 1H), 4.59 (ddd, J = 10.6, 8.2, 2.8 Hz, 1H), 3.27 (ddd, J =
17.8, 10.3, 5.1 Hz, 1H), 2.93 (ddd, J = 17.8, 10.3, 2.9 Hz, 1H), 1.99 (s, 3H); 13C{1H} NMR (CDCl3, 125 MHz): δ
204.8 (d, JC−P = 12.0 Hz), 137.5 (d, JC−P = 6.4 Hz), 132.1 (d, JC−P = 2.7 Hz), 131.7 (d, JC−P = 2.6 Hz), 131.4 (d, JC−P
= 6.5 Hz), 131.3 (d, JC−P = 8.4 Hz), 131.1 (d, JC−P = 9.0 Hz), 130.6 (d, JC−P = 12.7 Hz), 128.6 (d, JC−P = 90.8 Hz),
128.5 (d, JC−P = 90.8 Hz), 127.3 (d, JC−P = 6.4 Hz), 126.7 (d, JC−P = 2.5 Hz), 124.9 (d, JC−P = 2.7 Hz), 44.4, 36.3 (d,
JC−P = 70.1 Hz), 30.6; 31P{1H} NMR (CDCl3, 202 MHz): δ 32.5; IR (film) υmax 3056, 2913, 1714, 1178, 1116 cm−1;
HRMS (ESI-TOF) m/z [M + H]+ calcd for C20H19O2PSH+ 355.0916, found 355.0912.
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4-(Diphenylphosphinyl)-4-(pyridin-3-yl)butan-2-one (3r).29 42% yield, 58 mg; pale yellow solid; mp
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198.8−199.6 °C; H NMR (CDCl3, 500 MHz): δ 8.43 (m, 1H), 8.36 (m, 1H), 7.97−7.93 (m, 2H), 7.79−7.77 (m,
1H), 7.58−7.47 (m, 5H), 7.36−7.32 (m, 1H), 7.28−7.25 (m, 2H), 7.14−7.12 (m, 1H), 4.26 (ddd, J = 10.0, 7.2, 2.7
Hz, 1H), 3.29 (ddd, J = 18.1, 10.0, 5.1 Hz, 1H), 2.99 (ddd, J = 18.1, 11.1, 2.4 Hz, 1H), 1.97 (s, 3H); 13C{1H} NMR
(CDCl3, 125 MHz): δ 204.5 (d, JC−P = 12.6 Hz), 151.0 (d, JC−P = 6.4 Hz), 148.4 (d, JC−P = 1.9 Hz), 136.6 (d, JC−P
=
5.0 Hz), 132.3 (d, JC−P = 2.7 Hz), 132.1 (d, JC−P = 5.3 Hz), 131.8 (d, JC−P = 2.6 Hz), 131.3(d, JC−P = 14.5 Hz), 131.1
(d, JC−P = 8.8 Hz), 130.7 (d, JC−P = 8.8 Hz), 130.5 (d, JC−P = 9.3 Hz), 128.7 (d, JC−P = 79.9 Hz), 128.6 (d, JC−P
=
80.5 Hz), 123.2 (d, JC−P = 1.8 Hz), 43.2, 38.1 (d, JC−P = 67.8 Hz), 30.3; 31P{1H} NMR (CDCl3, 202 MHz): δ 33.1;
IR (film) υmax 2923, 1730, 1181, 1112 cm−1; HRMS (ESI-TOF) m/z [M + H]+ calcd for C21H20NO2PH+ 350.1304,
found 350.1303.
4-(Diphenylphosphinyl)-4-(benzothiophen-3-yl)butan-2-one (3s). 92% yield, 149 mg; white solid; mp
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192.4−192.7 °C; H NMR (CDCl3, 500 MHz): δ 7.99−7.95 (m, 2H), 7.87−7.85 (m, 1H), 7.71−7.68 (m, 2H),
7.55−7.49 (m, 3H), 7.45−7.41 (m, 2H), 7.27−7.24 (m, 1H), 7.22−7.19 (m, 1H), 7.15−7.11 (m, 1H), 7.07−7.03 (m,
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2H), 4.80 (ddd, J = 9.0, 7.4, 3.3 Hz, 1H), 3.29 (ddd, J = 17.9, 8.8, 6.7 Hz, 1H), 3.11 (ddd, J = 17.9, 11.7, 3.3 Hz,
1H), 1.88 (s, 3H); 13C{1H} NMR (CDCl3, 125 MHz): δ 205.0 (d, JC−P = 11.0 Hz), 139.6, 138.4 (d, JC−P = 5.2 Hz),
132.1 (d, JC−P = 2.3 Hz), 131.7 (d, JC−P = 26.3 Hz), 131.5, 131.4 (d, JC−P = 8.6 Hz), 131.1 (d, JC−P = 5.5 Hz), 130.9
(d, JC−P = 20.1 Hz), 130.6 (d, JC−P = 9.1 Hz), 128.5 (d, JC−P = 113.5 Hz), 128.4 (d, JC−P = 114.0 Hz), 125.4 (d, JC−P
= 6.4 Hz), 124.1 (d, JC−P = 35.9 Hz), 122.5, 121.8, 44.1, 33.3 (d, JC−P = 69.7 Hz), 30.2; 31P{1H} NMR (CDCl3, 202
MHz): δ 33.2; IR (film) υmax 3053, 2919, 1715, 1185, 1115 cm−1; HRMS (ESI-TOF) m/z [M + H]+ calcd for
C24H21O2PSH+ 405.1073, found 405.1075.
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4-(Diphenylphosphinyl)nonan-2-one (3t).32 91% yield, 125 mg; colorless oil; H NMR (CDCl3, 500 MHz): δ
7.86−7.78 (m, 4H), 7.49−7.41 (m, 6H), 3.20−3.14 (m, 1H), 2.79 (ddd, J = 19.1, 16.2, 3.8 Hz, 1H), 2.68−2.61 (m,
1H), 1.98 (s, 3H), 1.67−1.58 (m, 1H), 1.53−1.43 (m, 1H), 1.29−1.08 (m, 6H), 0.78 (t, J = 6.9 Hz, 3H); 13C{1H}
NMR (CDCl3, 125 MHz): δ 205.9 (d, JC−P = 9.7 Hz), 132.3(d, JC−P = 95.4 Hz), 132.2 (d, JC−P = 96.3 Hz), 131.7 (d,
JC−P = 2.7 Hz), 131.6 (d, JC−P = 2.7 Hz), 130.9, 130.9 (d, JC−P = 17.3 Hz), 128.7 (d, JC−P = 10.9 Hz), 128.6 (d, JC−P
= 10.9 Hz), 41.8, 31.6 (d, JC−P = 72.4 Hz), 31.5, 30.0, 28.5, 27.2 (d, JC−P = 10.8 Hz), 22.2, 13.8; 31P{1H} NMR
(CDCl3, 202 MHz): δ 36.7; IR (film) υmax 3057, 2929, 1717, 1190, 1116 cm−1; HRMS (ESI-TOF) m/z [M + H]+
calcd for C21H27O2PH+ 343.1821, found 343.1823.
4-(Diphenylphosphinyl)-4-cyclohexylbutan-2-one (3u). 85% yield, 121 mg; white solid; mp 212.1−214.3 °C; 1H
NMR (CDCl3, 500 MHz): δ 7.88−7.84 (m, 2H), 7.80−7.77 (m, 2H), 7.51−7.38 (m, 6H), 3.21−3.17 (m, 1H), 2.76
(dd, J = 13.7 Hz, 5.2 Hz, 2H), 2.11−2.09 (m, 2H), 1.92 (s, 3H), 1.75−1.61 (m, 3H), 1.55−1.50 (m, 2H), 1.14−0.94
(m, 5H); 13C{1H} NMR (CDCl3, 125 MHz): δ 206.4 (d, JC−P = 8.2 Hz), 132.9 (d, JC−P = 94.3 Hz), 132.8 (d, JC−P
=
95.6 Hz), 131.5 (d, JC−P = 6.2 Hz), 131.5, 131.0 (d, JC−P = 8.5 Hz), 130.8 (d, JC−P = 8.8 Hz), 128.6 (d, JC−P = 11.0
Hz), 128.5 (d, JC−P = 11.1 Hz), 37.9, 37.7 (d, JC−P = 1.2 Hz), 36.3 (d, JC−P = 71.3 Hz), 32.8 (d, JC−P = 12.6 Hz), 29.8,
29.4 (d, JC−P = 2.4 Hz), 26.6, 26.3, 26.0; 31P{1H} NMR (CDCl3, 202 MHz): δ 36.4; IR (film) υmax 3054, 2925,
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4-(Diphenylphosphinyl)-5-phenylpentan-2-one (3v). 77% yield, 112 mg; white solid; mp 178.2−180.3 °C; H
NMR (CDCl3, 500 MHz): δ 7.92−7.83 (m, 4H), 7.48−7.40 (m, 6H), 7.19−7.10 (m, 5H), 3.62−3.56 (m, 1H), 2.98.
(ddd, J = 13.6, 8.0, 4.7 Hz, 1H), 2.81−2.68 (m, 2H), 2.60 (ddd, J = 18.0, 9.4, 6.4 Hz, 1H), 1.62 (s, 3H); 13C{1H}
NMR (CDCl3, 125 MHz): δ 205.5 (d, JC−P = 8.1 Hz), 138.2 (d, JC−P = 13.0 Hz), 131.8 (d, JC−P = 2.4 Hz), 131.8 (d,
JC−P = 2.4 Hz), 131.7 (d, JC−P = 96.1 Hz), 131.7 (d, JC−P = 96.3 Hz), 131.1 (d, JC−P = 8.8 Hz), 130.9 (d, JC−P = 8.7
Hz), 129.3, 128.8, 128.7 (d, JC−P = 1.8 Hz), 128.6, 128.4, 126.6, 40.7, 34.0, 33.3 (d, JC−P = 71.3 Hz), 29.7; 31P{1H}
NMR (CDCl3, 202 MHz): δ 36.1; IR (film) υmax 3054, 2924, 1714, 1179, 1117 cm−1; HRMS (ESI-TOF) m/z [M +
H]+ calcd for C23H23O2PH+ 363.1508, found 363.1509.
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4-(Diphenylphosphinyl)-6-phenylhex-5-en -2-one (3w). 86% yield, 129 mg; white solid; mp 202.5−205.7 °C; 1H
NMR (CDCl3, 500 MHz): δ 7.88−7.85 (m, 2H), 7.78−7.75 (m, 2H), 7.53−7.40 (m, 6H), 7.22−7.17 (m, 5H), 6.38
(dd, J = 15.9 Hz, 3.9 Hz, 1H), 6.07 (ddd, J = 15.7, 9.0, 6.5 Hz, 1H), 3.98−3.92 (m, 1H), 2.98 (ddd, J = 17.3, 9.4,
5.1 Hz, 1H), 2.88−2.82 (m, 1H), 2.06−2.05 (m, 3H); 13C{1H} NMR (CDCl3, 125 MHz): δ 205.2 (d, JC−P = 12.4
Hz), 136.5 (d, JC−P = 2.6 Hz), 135.2 (d, JC−P = 11.6 Hz), 132.1 (d, JC−P = 1.8 Hz), 131.8 (d, JC−P = 2.6 Hz), 131.4 (d,
JC−P = 95.4 Hz), 131.4 (d, JC−P = 8.7 Hz), 131.2 (d, JC−P = 8.6 Hz), 131.2 (d, JC−P = 99.4 Hz), 128.9 (d, JC−P = 11.2
Hz), 128.5, 128.5 (d, JC−P = 11.5 Hz), 127.7, 126.3, 123.3 (d, JC−P = 7.3 Hz), 41.7, 38.6 (d, JC−P = 69.8 Hz), 30.6;
31P{1H} NMR (CDCl3, 202 MHz): δ 33.7; IR (film) υmax 3053, 2921, 1714, 1182, 1116 cm−1; HRMS (ESI-TOF)
m/z [M + H]+ calcd for C24H23O2PH+ 375.1508, found 375.1509.
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4-(Diphenylphosphinyl)-6-phenylhex-5-yn -2-one (3x). 55% yield, 82 mg; yellow oil; H NMR (CDCl3, 500
MHz): δ 7.99−7.91 (m, 4H), 7.59−7.54 (m, 2H), 7.51−7.48 (m, 4H), 7.26−7.16 (m, 5H), 4.19 (ddd, J = 16.6, 10.4,
2.9 Hz, 1H), 3.16 (ddd, J = 17.5, 9.6, 2.9 Hz, 1H), 2.88 (ddd, J = 17.1, 10.4, 5.2 Hz, 1H), 2.19 (s, 3H); 13C{1H}
NMR (CDCl3, 125 MHz): δ 204.2 (d, JC−P = 11.6 Hz), 132.4−132.3 (m), 131.9 (d, JC−P = 93.0 Hz), 131.8 (d, JC−P
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93.6 Hz), 130.7, 130.3, 129.5, 128.7 (d, JC−P = 12.1 Hz), 127.4, 128.3, 128.2, 122.6 (d, JC−P = 3.4 Hz), 85.7 (d, JC−P
= 8.3 Hz), 85.2 (d, JC−P = 7.7 Hz), 41.9, 30.2, 29.0 (d, JC−P = 70.6 Hz); 31P{1H} NMR (CDCl3, 202 MHz): δ 31.8;
IR (film) υmax 3054, 2922, 1714, 1180, 1118 cm−1; HRMS (ESI-TOF) m/z [M + H]+ calcd for C24H21O2PH+
373.1352, found 373.1353.
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4-(Diphenylphosphinyl)-4-methyldecan-2-one (3y). 79% yield, 117 mg; colorless oil; H NMR (CDCl3, 500
MHz): δ 8.02−7.96 (m, 4H), 7.54−7.46 (m, 6H), 3.07 (dd, J = 16.3, 9.5 Hz, 1H), 2.55 (dd, J = 16.3, 10.6 Hz, 1H),
2.09 (s, 3H), 2.81−2.75 (m, 2H), 1.42 (d, J = 16.8 Hz, 3H), 1.38 (m, 1H), 1.19−1.12 (m, 7H), 0.81 (t, J = 7 Hz, 3H);
13C{1H} NMR (CDCl3, 125 MHz): δ 206.8 (d, JC−P = 12.4 Hz), 132.2, 132.1, 131.6 (d, JC−P = 2.6Hz), 131.5 (d,
JC−P = 2.6 Hz), 131.4 (d, JC−P = 89.2 Hz), 131.0 (d, JC−P = 90.0 Hz), 128.4, 128.3, 44.7, 40.3 (d, JC−P = 67.7 Hz),
34.9, 32.3, 31.4, 29.8, 24.4 (d, JC−P = 4.9 Hz), 22.4, 21.0, 14.0; 31P{1H} NMR (CDCl3, 202 MHz): δ 36.5; IR (film)
υmax 3055, 2924, 1714, 1177 cm−1; HRMS (ESI-TOF) m/z [M + H]+ calcd for C23H31O2PH+ 371.2134, found
371.2133.
4-Methyl-4-(diphenylphosphinyl)-4-phenylbutan-2-one (3z). 99% yield, 142 mg; colorless oil; 1H NMR (CDCl3,
500 MHz): δ 7.65−7.61 (m, 2H), 7.54−7.48 (m, 3H), 7.45−7.37 (m, 3H), 7.33−7.29 (m, 2H), 7.23−7.18 (m, 3H),
7.09−7.07 (m, 2H), 3.58 (dd, J = 16.9, 7.9 Hz, 1H), 3.12 (dd, J = 5.4, 16.9 Hz, 1H), 1.90 (s, 3H), 1.79 (d, J = 16.4
Hz, 3H); 13C{1H} NMR (CDCl3, 125 MHz): δ 205.1 (d, JC−P = 15.4 Hz), 138.4 (d, JC−P = 3.3 Hz), 132.9 (d, JC−P
=
7.3 Hz), 132.7 (d, JC−P = 8.0 Hz), 131.9 (d, JC−P = 2.6 Hz), 131.8 (d, JC−P = 2.8 Hz), 129.6 (d, JC−P = 93.1 Hz),
129.2 (d, JC−P = 92.0 Hz), 128.3 (d, JC−P = 4.9 Hz), 128.1 (d, JC−P = 10.9 Hz), 127.9 (d, JC−P = 11.3 Hz), 127.9 (d,
JC−P = 2.9 Hz), 127.1 (d, JC−P = 3.6Hz), 47.3, 44.4 (d, JC−P = 63.1 Hz), 31.8 (d, JC−P = 1.5 Hz), 19.6; 31P{1H} NMR
(CDCl3, 202 MHz): δ 35.1; IR (film) υmax 3056, 2928, 1705, 1176, 1107 cm−1; HRMS (ESI-TOF) m/z [M + H]+
calcd for C23H23O2PH+ 363.1508, found 363.1506.
1-(1-Diphenylphosphinylcyclohexyl)propan-2-one (3aa). 89% yield, 121 mg; white solid; mp 153.3−155.9 °C;
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1H NMR (CDCl3, 500 MHz): δ 8.02−7.98 (m, 4H), 7.53−7.45 (m, 6H), 2.82 (d, J = 19.2 Hz, 2H), 2.24−2.22 (m,
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2H), 2.00 (s, 3H), 1.64−1.46 (m, 7H), 1.08−1.00 (m, 1H); 13C{1H} NMR (CDCl3, 125 MHz): δ 207.6 (d, JC−P
=
8
9
Hz), 132.3 (d, JC−P = 8.1 Hz), 131.6 (d, JC−P = 2.3 Hz), 130.9, 128.2 (d, JC−P = 10.9 Hz), 43.1, 42.6, 41.2, 32.5, 29.7,
26.5, 25.2, 20.8 (d, JC−P = 10.8 Hz); 31P{1H} NMR (CDCl3, 202 MHz): δ 35.5; IR (film) υmax 3056, 2925, 1722,
1179, 1109 cm−1; HRMS (ESI-TOF) m/z [M + H]+ calcd for C21H25O2PH+ 341.1665, found 341.1665.
3-Methyl-4-(diphenylphosphinyl)-4-phenylbutan-2-one (3ab). 87% yield, 126 mg; white solid; mp 175.9−177.2
°C; 1H NMR (CDCl3, 500 MHz): δ 7.92−7.89 (m, 2H), 7.55−7.45 (m, 5H), 7.35−7.33 (m, 2H), 7.28−7.26 (m, 1H),
7.22−7.19 (m, 2H), 7.16−7.09 (m, 3H), 4.36 (dd, J = 7.8, 7.8 Hz, 1H), 3.46−3.38 (m, 1H), 1.92 (s, 3H), 1.02 (d, J =
7.2 Hz, 3H); 13C{1H} NMR (CDCl3, 125 MHz): δ 210.6 (d, JC−P = 5.5 Hz), 134.4 (d, JC−P = 4.6 Hz), 132.4 (d, JC−P
= 94.5 Hz), 132.1 (d, JC−P = 99.1 Hz), 131.8 (d, JC−P = 2.6 Hz), 131.6 (d, JC−P = 8.8 Hz), 131.1 (d, JC−P = 4.5 Hz),
131.1 (d, JC−P = 5.9 Hz), 131.0, 128.5 (d, JC−P = 11.5 Hz), 128.2, 128.0 (d, JC−P = 11.7 Hz), 127.1(d, JC−P = 1.5 Hz),
46.3 (d, JC−P = 67.7 Hz), 45.6, 28.8, 16.0 (d, JC−P = 6.7 Hz); 31P{1H} NMR (CDCl3, 202 MHz): δ 32.4; IR (film)
υmax 3054, 2924, 1712, 1170, 1115 cm−1; HRMS (ESI-TOF) m/z [M + H]+ calcd for C23H23O2PH+ 363.1508, found
363.1509.
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4-(Diphenylphosphinyl)-1,1,4-triphenylbutan-2-one (3ac). 56% yield, 112 mg; white solid; mp 203.8−206.3 °C;
1H NMR (CDCl3, 500 MHz): δ 7.90−7.87 (m, 2H), 7.57−7.49 (m, 3H), 7.40−7.37 (m, 2H), 7.31−7.29 (m, 1H),
7.21−7.08 (m, 13H), 6.96−6.94 (m, 2H), 6.75−6.73 (m, 2H), 4.85 (s, 1H), 4.25−4.22 (m, 1H), 3.46 (ddd, J = 17.2,
10.7, 2.2 Hz, 1H), 2.99−2.94 (m, 1H); 13C{1H} NMR (CDCl3, 125 MHz): δ 205.3 (d, JC−P = 13.2 Hz), 137.7, 136.9,
135.2, 132.0, 131.4, 131.3 (d, JC−P = 8.2 Hz), 130.9 (d, JC−P = 9.2 Hz), 129.9 (d, JC−P = 5.4 Hz), 129.0 (d, JC−P
=
11.2 Hz), 128.9 (d, JC−P = 7.7 Hz), 128.7, 128.5, 128.3, 128.1 (d, JC−P = 11.5 Hz), 127.2, 127.1, 64.6, 42.7, 41.3 (d,
JC−P = 68.2 Hz); 31P{1H} NMR (CDCl3, 202 MHz): δ 33.5; IR (film) υmax 3054, 22921, 1715, 1182, 1117 cm−1;
HRMS (ESI-TOF) m/z [M + H]+ calcd for C34H29O2PH+ 501.1978, found 501.1978.
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4-(Diphenylphosphinyl)-1,4-diphenylbutan-2-one (3ad). 25% yield, 42 mg; white solid; mp 251.6−253.2 °C; 1H
NMR (CDCl3, 500 MHz): δ 7.83−7.79 (m, 2H), 7.48−7.40 (m, 3H), 7.35−7.31 (m, 2H), 7.25−7.22 (m, 1H),
7.15−7.09 (m, 7H), 7.03−7.02 (m, 3H), 6.80−6.79 (m, 2H), 4.12 (ddd, J = 10.1, 7.3, 2.8 Hz, 1H), 3.38 (dd, J = 22.9,
15.3 Hz, 2H), 3.27 (ddd, J = 17.6, 10.2, 5.5 Hz, 1H), 2.85 (ddd, J = 17.7, 11.0, 2.9 Hz, 1H); 13C{1H} NMR (CDCl3,
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125 MHz): δ 205.1 (d, JC−P = 12.7 Hz), 135.5 (d, JC−P = 5.5 Hz), 133.1, 132.0 (d, JC−P = 2.7 Hz), 131.8 (d, JC−P
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24.5 Hz), 131.4 (d, JC−P = 2.4 Hz), 131.3 (d, JC−P = 8.7 Hz), 131.1, 131.0 (d, JC−P = 9.0 Hz), 129.7 (d, JC−P = 5.7
Hz), 129.3, 128.7, 128.5 (d, JC−P = 101.7 Hz), 128.4 (d, JC−P = 102.4 Hz), 128.3, 127.1 (d, JC−P = 1.9 Hz), 127.0,
50.5, 41.9, 41.0 (d, JC−P = 68.4 Hz);31P{1H} NMR (CDCl3, 202 MHz): δ 33.6; IR (film) υmax 3063, 2926, 1714,
1190, 1117 cm−1; HRMS (ESI-TOF) m/z [M + H]+ calcd for C28H25O2PH+ 425.1665, found 425.1658.
1
7-(Diphenylphosphinyl)dodecan-5-one (3ae). 42% yield, 65 mg; colorless oil; H NMR (CDCl3, 500 MHz): δ
7.86−7.78 (m, 4H), 7.51−7.41 (m, 6H), 3.23−3.17 (m, 1H), 2.80−2.73 (m, 1H), 2.64−2.57 (m, 1H), 2.31−2.24 (m,
1H), 2.18−2.12 (m, 1H), 1.67−1.58 (m, 1H), 1.53−1.32 (m, 3H), 1.29−1.09 (m, 8H), 0.82 (t, J = 7.3 Hz, 3H), 0.78
(t, J = 6.9 Hz, 3H); 13C{1H} NMR (CDCl3, 125 MHz): δ 208.5 (d, JC−P = 9.3 Hz), 132.3 (d, JC−P = 95.8 Hz), 132.3
(d, JC−P = 95.0 Hz), 131.6, 131.6 (d, JC−P = 4.5 Hz), 131.0 (d, JC−P = 8.2 Hz), 130.9 (d, JC−P = 8.2 Hz), 128.7, 128.6,
42.7, 40.9, 31.5, 30.9, 28.5 (d, JC−P = 1.4 Hz), 27.2 (d, JC−P = 10.8 Hz), 25.8, 22.2, 22.1, 13.8, 13.7; 31P{1H} NMR
(CDCl3, 202 MHz): δ 36.7; IR (film) υmax 2920, 2851, 1714, 1166, 1118 cm−1; HRMS (ESI-TOF) m/z [M + H]+
calcd for C24H33O2PH+ 385.2291, found 385.2290.
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1-(Diphenylphosphinyl)-1-phenylheptan-3-one (3af).6 90% yield, 141 mg; white solid; mp 182.7−185.1 °C; H
NMR (CDCl3, 500 MHz): δ 7.88−7.85 (m, 2H), 7.50−7.43 (m, 3H), 7.38−7.35 (m, 2H), 7.25−7.21 (m, 3H),
7.17−7.14 (m, 2H), 7.09−7.03 (m, 3H), 4.17 (ddd, J = 9.8, 7.0, 2. Hz, 1H), 3.23 (ddd, J = 17.6, 10.1, 5.5 Hz, 1H),
2.82 (ddd, J = 17.6, 11.3, 2.7 Hz, 1H), 2.17−2.03 (m, 2H), 1.30−1.21 (m, 2H), 1.02−0.95 (m, 2H), 0.67 (t, J = 7.3
Hz, 3H); 13C{1H} NMR (CDCl3, 125 MHz): δ 207.9 (d, JC−P = 12.3 Hz), 135.9 (d, JC−P = 5.5 Hz), 132.0 (d, JC−P
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2.7 Hz), 131.8, 131.4 (d, JC−P = 2.7 Hz), 131.3 (d, JC−P = 9.1 Hz), 131.1 (d, JC−P = 13.2 Hz), 131.0 (d, JC−P = 8.8
Hz), 129.7 (d, JC−P = 6.4 Hz), 128.5 (d, JC−P = 100.3 Hz), 128.4 (d, JC−P = 100.9 Hz), 128.3 (d, JC−P = 1.3 Hz),
127.1 (d, JC−P = 2.4 Hz), 43.3, 42.6, 40.8 (d, JC−P = 68.4 Hz), 25.6, 22.0, 13.7; 31P{1H} NMR (CDCl3, 202 MHz): δ
33.8; IR (film) υmax 3048, 2918, 1715, 1184, 1118 cm−1; HRMS (ESI-TOF) m/z [M + H]+ calcd for C25H27O2PH+
391.1821, found 391.1823.
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1-(Diphenylphosphinyl)-1-(4-chlorophenyl)heptan-3-one (3ag). 85% yield, 127 mg; white solid; mp
1
217.9−219.9 °C; H NMR (CDCl3, 500 MHz): δ 7.84−7.90 (m, 2H), 7.58−7.51 (m, 3H), 7.48−7.45 (m, 2H),
7.37−7.35 (m, 1H), 7.29−7.24 (m, 4H), 7.14−7.13 (m, 2H), 4.22 (m, 1H), 3.24 (ddd, J = 16.8, 9.9, 3.7 Hz, 1H),
2.90−2.84 (m, 1H), 2.25−2.12 (m, 2H), 1.36−1.29 (m, 2H), 1.11−1.04 (m, 2H), 0.76 (t, J = 7.3 Hz, 3H); 13C{1H}
NMR (CDCl3, 125 MHz): δ 207.5 (d, JC−P = 11.9 Hz), 134.7 (d, JC−P = 5.1 Hz), 133.0 (d, JC−P = 1.5 Hz), 132.1,
131.6, 131.3, 131.2, 131.0 (d, JC−P = 4.5 Hz), 130.9, 130.8, 128.6 (d, JC−P = 86.3 Hz), 128.5 (d, JC−P = 87.1 Hz),
128.5, 43.2, 42.6, 40.1 (d, JC−P = 68.0 Hz), 25.5, 22.0, 13.7; 31P{1H} NMR (CDCl3, 202 MHz): δ 33.2; IR (film)
υmax 2922, 1737, 1183, 1122 cm−1; HRMS (ESI-TOF) m/z [M + H]+ calcd for C25H26ClO2PH+ 425.1432, found
425.1433.
1-(Diphenylphosphinyl)-1-(4-methylphenyl)heptan-3-one (3ah). 88% yield, 139 mg; white solid; mp
1
182.6−183.8 °C; H NMR (CDCl3, 500 MHz): δ 7.86−7.82 (m, 2H), 7.43−7.37 (m, 5H), 7.24−7.21 (m, 1H),
7.16−7.10 (m, 4H), 6.89−6.86 (m, 2H), 4.16−4.12 (m, 1H), 3.18 (ddd, J = 17.6, 10.0, 5.5 Hz, 1H), 2.79 (ddd, J =
17.3, 11.2, 2.4 Hz, 1H), 2.12 (s, 3H), 2.15−2.01 (m, 2H), 1.26−1.20 (m, 2H), 1.01−0.94 (m, 2H), 0.65 (t, J = 7.4
Hz, 3H); 13C{1H} NMR (CDCl3, 125 MHz): δ 207.9 (d, JC−P = 12.2 Hz), 136.6 (d, JC−P = 2.3 Hz), 132.7 (d, JC−P
5.4 Hz), 132.1 (d, JC−P = 3.9 Hz), 131.9 (d, JC−P = 2.1 Hz), 131.3, 131.2, 131.0 (d, JC−P = 8.7 Hz), 129.6 (d, JC−P
5.4 Hz), 129.0 (d, JC−P = 1.5 Hz), 128.5 (d, JC−P = 94.9 Hz), 128.4 (d, JC−P = 94.9 Hz), 43.3, 42.7, 40.3 (d, JC−P
=
=
=
68.8Hz), 25.5, 22.0, 21.0, 13.7; 31P{1H} NMR (CDCl3, 202 MHz): δ 33.6; IR (film) υmax 2922, 1714, 1184, 1121
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cm−1; HRMS (ESI-TOF) m/z [M + H]+ calcd for C26H29O2PH+ 405.1978, found 405.1977.
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1-(Diphenylphosphinyl)-1-(4-(trifluoromethyl)phenyl)heptan-3-one (3ai). 57% yield, 104.5 mg; white solid; mp
8
9
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225.5−227.2 °C; H NMR (CDCl3, 500 MHz): δ 7.97−7.93 (m, 2H), 7.59−7.52 (m, 3H), 7.49−7.41 (m, 6H),
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7.36−7.33 (m, 1H), 7.26−7.24 (m, 2H), 4.35−4.32 (m, 1H), 3.31 (ddd, J = 17.8, 10.1, 5.1 Hz, 1H), 2.93 (ddd, J =
17.8, 11.6, 2.2 Hz, 1H), 2.26−2.13 (m, 2H), 1.36−1.29 (m, 2H), 1.10−1.03 (m, 2H), 0.74 (t, J = 7.4 Hz, 3H);
13C{1H} NMR (CDCl3, 125 MHz): δ 207.4 (d, JC−P = 11.8 Hz), 140.4 (d, JC−P = 4.2 Hz), 132.2 (d, JC−P = 1.6 Hz),
131.7 (d, JC−P = 2.7 Hz), 131.4 (d, JC−P = 24.9 Hz), 131.2 (d, JC−P = 8.4 Hz), 130.8 (d, JC−P = 9.1 Hz), 130.0 (d, JC−P
= 5.4 Hz), 129.2 (d, JC−P = 39.1 Hz), 128.7 (d, JC−P = 90.3 Hz), 128.6 (d, JC−P = 90.9 Hz), 125.2−125.1 (m), 123.0,
43.1, 42.5, 40.7 (d, JC−P = 67.2 Hz), 25.5, 22.0, 13.6; 31P{1H} NMR (CDCl3, 202 MHz): δ 33.2; IR (film) υmax
3054, 2922, 1714, 1175, 1111 cm−1; HRMS (ESI-TOF) m/z [M + H]+ calcd for C26H26F3O2PH+ 459.1695, found
459.1695.
4-(Bis(4-methylphenyl)phosphinyl)-4-phenylbutan-2-one (3aj). 99% yield, 149 mg; white solid; mp 170.0−171.9
°C; 1H NMR (CDCl3, 500 MHz): δ 7.79−7.75 (m, 2H), 7.36−7.32 (m, 2H), 7.30−7.28 (m, 2H), 7.24−7.22 (m, 2H),
7.13−7.07 (m, 3H), 6.98−6.96 (m, 2H), 4.22−4.18 (m, 1H), 3.31 (ddd, J = 17.5, 10.1, 5.5 Hz, 1H), 2.96 (ddd, J =
17.5, 11.2, 2.1 Hz, 1H), 2.34 (s, 3H), 2.20 (s, 3H), 1.89 (s, 3H); 13C{1H} NMR (CDCl3, 125 MHz): δ 205.7 (d, JC−P
= 12.6 Hz), 142.4 (d, JC−P = 2.5 Hz), 141.8 (d, JC−P = 2.6 Hz), 136.0 (d, JC−P = 5.4 Hz), 131.3 (d, JC−P = 9.1 Hz),
131.1 (d, JC−P = 9.1 Hz), 129.8 (d, JC−P = 5.6 Hz), 129.2 (d, JC−P = 93.6 Hz), 129.1 (d, JC−P = 94.6 Hz), 128.3, 127.5,
127.4, 127.0 (d, JC−P = 1.7 Hz), 43.5, 41.0 (d, JC−P = 68.6 Hz), 30.5, 21.5, 21.4; 31P{1H} NMR (CDCl3, 202 MHz):
δ 34.7; IR (film) υmax 3061, 2914, 1715, 1181, 1116 cm−1; HRMS (ESI-TOF) m/z [M + H]+ calcd for C24H25O2PH+
377.1665, found 377.1665.
4-(Bis(4-chlorophenyl)phosphinyl)-4-phenylbutan-2-one (3ak). 95% yield, 159 mg; white solid; mp
1
171.4−173.3 °C; H NMR (CDCl3, 500 MHz): δ 7.87−7.84 (m, 2H), 7.52−7.51 (m, 2H), 7.37−7.33 (m, 2H),
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7.29−7.28 (m, 2H), 7.23−7.15 (m, 5H), 4.23−4.19 (m, 1H), 3.31 (ddd, J = 17.7, 9.8, 5.5 Hz, 1H), 2.93 (ddd, J =
17.7, 11.8, 2.3 Hz, 1H), 1.97 (s, 3H); 13C{1H} NMR (CDCl3, 125 MHz): δ 204.8 (d, JC−P = 12.4 Hz), 138.9 (d, JC−P
= 2.9 Hz), 138.2 (d, JC−P = 3.4 Hz), 135.3 (d, JC−P = 5.4 Hz), 132.6 (d, JC−P = 9.2 Hz), 132.3 (d, JC−P = 9.7 Hz),
130.0 (d, JC−P = 20.9 Hz), 129.6 (d, JC−P = 5.6 Hz), 129.2 (d, JC−P = 15.4 Hz), 129.0 (d, JC−P = 103.4 Hz), 128.9 (d,
JC−P = 103.7 Hz), 128.6 (d, JC−P = 1.8 Hz), 127.4 (d, JC−P = 2.4 Hz), 43.4, 40.6 (d, JC−P = 69.4 Hz), 30.6; 31P{1H}
NMR (CDCl3, 202 MHz): δ 32.8; IR (film) υmax 2922, 1714, 1181, 1086 cm−1; HRMS (ESI-TOF) m/z [M + H]+
calcd for C22H19Cl2O2PH+ 417.0572, found 417.0572.
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4-(Bis(4-methoxyphenyl)phosphinyl)-4-phenylbutan-2-one (3al). 94% yield, 154 mg; colorless oil; H NMR
(CDCl3, 500 MHz): δ 7.83−7.79 (m, 2H), 7.32−7.26 (m, 4H), 7.18−7.11 (m, 3H), 7.01−7.00 (m, 2H), 6.72−6.71
(m, 2H), 4.15−4.12 (m, 1H), 3.74 (s, 3H), 3.72 (s, 3H), 3.29 (ddd, J = 17.4, 10.0, 5.3 Hz, 1H), 2.96 (ddd, J = 17.5,
11.3, 2.2 Hz, 1H), 1.94 (s, 3H); 13C{1H} NMR (CDCl3, 125 MHz): δ 205.6 (d, JC−P = 12.6 Hz), 162.4 (d, JC−P = 2.6
Hz), 161.9 (d, JC−P = 2.7 Hz), 136.2 (d, JC−P = 5.4 Hz), 133.1 (d, JC−P = 9.1 Hz), 132.9 (d, JC−P = 10.2 Hz), 129.7 (d,
JC−P = 5.4 Hz), 128.3 (d, JC−P = 1.5 Hz), 127.0 (d, JC−P = 1.8 Hz), 123.0 (d, JC−P = 48.7 Hz), 122.2 (d, JC−P = 43.6
Hz), 114.0 (d, JC−P = 99.9 Hz), 113.9 (d, JC−P = 101.2 Hz), 55.3, 55.1, 43.6, 41.3 (d, JC−P = 68.9 Hz), 30.5; 31P{1H}
NMR (CDCl3, 202 MHz): δ 34.2; IR (film) υmax 2924, 1714, 1179, 1118 cm−1; HRMS (ESI-TOF) m/z [M + H]+
calcd for C24H25O4PH+ 409.1563, found 409.1564.
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4-(Di-n-butylphosphinyl)-4-phenylbutan-2-one (3am).33 67% yield, 83 mg; yellow solid; mp 85.1−87.2 °C; H
NMR (CDCl3, 500 MHz): δ 7.32−7.29 (m, 4H), 7.25−7.23 (m, 1H), 3.61 (ddd, J = 13.1, 9.3, 3.8 Hz, 1H), 3.27
(ddd, J = 17.9, 10.0, 3.9 Hz, 1H), 3.21−3.14 (m, 1H), 2.09 (s, 3H), 1.74−1.52 (m, 4H), 1.48−1.29 (m, 6H),
1.26−1.20 (m, 2H), 0.94 (t, J = 7.3 Hz, 3H), 0.79 (t, J = 7.3 Hz, 3H); 13C{1H} NMR (CDCl3, 125 MHz): δ 205.4 (d,
JC−P = 10.1 Hz), 137.1 (d, JC−P = 4.5 Hz), 128.8, 128.7, 127.2 (d, JC−P = 2.1 Hz), 43.0, 39.8 (d, JC−P = 60.2 Hz),
30.3, 26.3 (d, JC−P = 62.8 Hz), 25.4 (d, JC−P = 65.4 Hz), 24.1, 24.0 (d, JC−P = 30.0 Hz), 23.9 (d, JC−P = 3.7 Hz), 23.5
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(d, JC−P = 3.8 Hz), 13.5, 13.4; 31P{1H} NMR (CDCl3, 202 MHz): δ 50.9; IR (film) υmax 3062, 2928, 1716, 1158,
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1093 cm−1; HRMS (ESI-TOF) m/z [M + H]+ calcd for C18H29O2PH+ 309.1978, found 309.1977.
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Ethyl (3-oxobutyl)(phenyl)phosphinate (3an). 12% yield, 16 mg; white solid; mp 80.2−82.9 °C; H NMR
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(CDCl3, 500 MHz): δ 7.51−7.47 (m, 2H), 7.18−7.13 (m, 5H), 6.99−6.97 (m, 3H), 3.76−3.67 (m, 3H), 3.12−3.09
(m, 1H), 2.99−2.92 (m, 1H), 1.91 (s, 3H), 1.08 (t, J = 6.9 Hz, 3H) and isomer: δ 7.44−7.29 (m, 5H), 7.24−7.20 (m,
2H), 7.05−7.01 (m, 3H), 4.08−4.00 (m, 1H), 3.89−3.77 (m, 2H), 3.26−3.20 (m, 1H), 3.08−3.04 (m, 1H), 2.01 (s,
3H), 1.22 (t, J = 6.9 Hz, 3H); 13C{1H} NMR (CDCl3, 125 MHz): δ 203.8 (d, JC−P = 14.0 Hz), 134.7 (d, JC−P = 7.1
Hz), 131.4, 131.2 (d, JC−P = 9.1 Hz), 128.4 (d, JC−P = 5.5 Hz), 128.3 (d, JC−P = 124.4 Hz), 127.3 (d, JC−P = 15.50
Hz), 127.3 (d, JC−P = 5.3 Hz), 126.1 (d, JC−P = 2.7 Hz), 60.2 (m), 41.6 (d, JC−P = 97.1 Hz), 41.6, 29.3, 15.3 (d,
JC−P = 6.0 Hz) and isomer: 204.2 (d, JC−P = 12.6 Hz), 134.2 (d, JC−P = 3.4 Hz), 131.4, 131.2 (d, JC−P = 9.1 Hz),
128.2 (d, JC−P = 6.1 Hz), 127.9 (d, JC−P = 125.3 Hz), 127.2, 127.2 (d, JC−P = 9.2 Hz), 126.0 (d, JC−P = 2.8 Hz), 60.2
(m), 41.4 (d, JC−P = 2.7 Hz), 41.1 (d, JC−P = 97.7 Hz), 29.5, 15.4 (d, JC−P = 6.1 Hz); 31P{1H} NMR (CDCl3, 202
MHz): δ 41.7 and isomer: δ 43.2; IR (film) υmax 2922, 1713, 1225, 1121 cm−1; HRMS (ESI-TOF) m/z [M + H]+
calcd for C18H21O3PH+ 317.1301, found 317.1302.
4-(tert-Butyl(phenyl)phosphinyl)-4-phenylbutan-2-one (3ap). 81% yield, 106 mg; white solid; 1H NMR (CDCl3,
500 MHz): δ 7.45−7.41 (m, 2H), 7.29−7.26 (m, 1H), 7.21−7.17 (m, 4H), 7.05 −7.02 (m, 2H), 7.00−6.96 (m, 1H),
4.23 (ddd, J = 9.7, 6.8, 3.2 Hz, 1H), 3.48 (ddd, J = 18.1, 9.7, 3.2 Hz, 1H), 3.17 (ddd, J = 18.2, 9.2, 5.3 Hz, 1H),
2.04 (s, 3H), 1.20 (d, J = 14.3 Hz, 9H) and isomer: δ 7.85−7.82 (m, 2H), 7.64 (d, J = 5.9 Hz, 2H), 7.56 −7.49 (m,
3H), 7.36−7.32 (m, 2H), 7.27−7.24 (m, 1H), 4.16−4.14 (m, 1H), 3.17 (ddd, J = 18.2, 9.2, 5.3 Hz, 1H), 2.62−2.56
(m, 1H), 1.81 (s, 3H), 0.84 (d, J = 15.0 Hz, 9H); 13C{1H} NMR (CDCl3, 125 MHz): δ 205.7 (d, JC−P = 10.6 Hz),
138.9 (d, JC−P = 5.1 Hz), 132.3 (d, JC−P = 7.2 Hz), 130.8 (d, JC−P = 2.8 Hz), 129.5 (d, JC−P = 5.7 Hz), 129.4 (d, JC−P
= 88.0 Hz), 128.2, 127.3 (d, JC−P = 11.0 Hz), 126.6 (d, JC−P = 1.8 Hz), 46.0, 37.4 (d, JC−P = 58.9 Hz), 34.7 (d, JC−P
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= 63.7 Hz), 30.7, 25.5 and isomer: δ 205.4 (d, JC−P = 11.9 Hz), 137.6 (d, JC−P = 4.5 Hz), 131.7 (d, JC−P = 6.4 Hz),
131.6, 130.6 (d, JC−P = 82.7 Hz), 130.1 (d, JC−P = 5.0 Hz), 128.7, 128.5 (d, JC−P = 10.3 Hz), 127.4, 46.0, 37.3 (d,
JC−P = 60.3 Hz), 33.1 (d, JC−P = 67.0 Hz), 30.6, 24.9; 31P{1H} NMR (CDCl3, 202 MHz): δ 49.8 and isomer: δ 51.3;
IR (film) υmax 3060, 2973, 1714, 1362, 1157 cm−1; HRMS (ESI-TOF) m/z [M + H]+ calcd for C20H25O2PH+
329.1665, found 329.1662.
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The Procedure for the Synthesis of 4. To a stirred solution of the 3a (1 mmol) in 1.7 mL of DMSO was added
slowly 0.44 mL (3 mmol) of 48% aqueous HBr. The solution was stirred in an open flask at 55 °C in an oil bath
for 4h. Then the solution was poured onto ice. The solid products were filtered, washed with water, and dried
under vacuum. The resulting mixture was purified by silica gel chromatography to afford 4.
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3-bromo-4-(Diphenylphosphinyl)-4-phenylbutan-2-one (4). 56% yield, 239 mg; white solid; H NMR (CDCl3,
500 MHz): δ 7.89−7.85 (m, 2H), 7.54−7.52 (m, 1H), 7.50−7.46 (m, 2H), 7.43−7.40 (m, 2H), 7.34−7.31 (m, 1H),
7.23−7.19 (m, 2H), 7.14−7.08 (m, 5H), 5.19 (dd, J = 11.3, 7.4 Hz, 1H), 4.68 (dd, J = 11.3, 10.3 Hz, 1H), 2.29 (s,
3H); 13C{1H} NMR (CDCl3, 125 MHz): δ 199.6, 135.0 (d, JC−P = 4.6 Hz), 132.4, 132.2 (d, JC−P = 2.7 Hz), 131.6
(d, JC−P = 2.9 Hz), 131.5 (d, JC−P = 7.4 Hz), 130.9, 130.3 (d, JC−P = 5.2 Hz), 130.1, 128.4 (d, JC−P = 87.5 Hz), 128.3
(d, JC−P = 87.8 Hz), 128.2 (d, JC−P = 1.6 Hz), 127.6 (d, JC−P = 2.5 Hz), 52.8 (d, JC−P = 6.1 Hz), 50.0 (d, JC−P = 57.9
Hz), 27.4; 31P{1H} NMR (CDCl3, 202 MHz): δ 3.9; HRMS (ESI-TOF) m/z [M + H]+ calcd for C22H20BrO2PH+
427.0457, found 427.0455.
The Procedure for the Synthesis of 5. To a Schlenk tube equipped with a magnetic stir bar were added
1-phenyl-2,3-butadien-1-ol (1 mmol) and TfOH (0.3 mmol) in THF (5 mL) under argon, and the mixture was kept
stirring at 100 °C in an oil bath for 24 h. The resulting mixture was directly purified by silica gel chromatography
to afford 5.
(E)-4-Phenyl-3-buten-2-one (5). 51% yield, 75 mg; yellow liquid; 1H NMR (CDCl3, 500 MHz): δ 7.54−7.52 (m,
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2H), 7.50 (d, J = 13.7 Hz, 1H),7.39−7.37 (m, 3H), 6.70 (d, J = 16.4 Hz, 1H), 2.37 (s, 3H); 13C{1H} NMR (CDCl3,
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125 MHz): δ 198.4, 143.4, 134.4, 130.5, 129.0, 128.3, 127.1, 27.5; HRMS (ESI-TOF) m/z [M + H]+ calcd for
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C10H10OH+ 147.0804, found 147.0804.
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The Procedure for the Synthesis of 3a via the Addition of 2a to 5. To a Schlenk tube equipped with a magnetic
stir bar were added 4 (0.4 mmol), diphenylphosphine oxide (0.48 mmol) and TfOH (0.12 mmol) in THF (2 mL)
under argon, and the mixture was kept stirring at 100 °C in an oil bath for 24 h. The resulting mixture was directly
purified by silica gel chromatography using a mixture of petroleum ether and ethyl acetate as eluent to afford 3a.
ASSOCIATED CONTENT
Supporting Information
The Supporting Information is available free of charge at http://pubs.acs.org.
X-ray crystallographic data for compounds 3e and copies of NMR spectra for all products (PDF)
Crystallographic data for compound 3e (CIF)
AUTHOR INFORMATION
Correspongding Authors
*E-mail: gaoxingchem@xmu.edu.cn
*E-mail: xpengxiang@xmu.edu.cn.
ORCID
Yuxing Gao: 0000-0002-6420-0656
Yufen Zhao: 0000-0002-8513-1354
Notes
The authors declare no competing financial interest.
ACKNOWLEDGMENTS
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This work was supported by the Chinese National Natural Science Foundation (21202135, 21642010, 41576081)
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and the Fundamental Research Funds for the Central Universities (20720180083, 20720160034)。
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REFERENCES
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Hepatitis C Virus NS3 Protease Inhibitors. Bioorg. Med. Chem. Lett. 2009, 19, 3453. (b) Leung, P.-H. Asymmetric
Synthesis and Organometallic Chemistry of Functionalized Phosphines Containing Stereogenic Phosphorus
Centers. Acc. Chem. Res. 2004, 37, 169. (c) Queffelec, C.; Petit, M.; Janvier, P.; Knight, D. A.; Bujoli, B. Surface
Modification Using Phosphonic Acids and Esters. Chem. Rev. 2012, 112, 3777. (d) Chen, X.; Kopecky, D. J.;
Mihalic, J.; Jeffries, S.; Min, X.; Heath, J.; Deignan, J.; Lai, S.; Fu, Z.; Guimaraes, C.; Shen, S.; Li, S.; Johnstone,
S.; Thibault, S.; Xu, H.; Cardozo, M.; Shen, W.; Walker, N.; Kayser, F.; Wang, Z. Structure-Guided Design,
Synthesis, and Evaluation of Guanine-Derived Inhibitors of the eIF4E mRNA-Cap Interaction. J. Med. Chem.
2012, 55, 3837. (e) Zhou, Z.; Liu, J.; Lu, X. Xie, P.; Fan, J.; Liu, Y.; Wo, X.; Fu, W.; Loh, T.-P. Bronsted
Acid/Organic Photoredox Cooperative Catalysis: Easy Access to Tri- and Tetrasubstituted Alkenylphosphorus
Compounds from Alcohols and P−H Species. Org. Lett. 2018, 20, 3341. (f) Wo, X.; Xie, P.; Fu, W.; Gao, C.; Liu,
Y.; Sun, Z.; Loh, T.-P. Barium-catalyzed C−OH/P−H dehydrative cross-coupling for C−P bond construction.
Chem. Commun. 2018, 54, 11132. (g) Chen, L.; Zou, Y.-X.; Liu, X.-Y.; Gou, X.-J. Dehydrative Cross-Coupling
and Related Reactions between Alcohols (C−OH) and P(O)−H Compounds for C−P Bond Formation. Adv. Synth.
Catal. 2019, 361, 3490.
(2) For representative publications, see: (a) Mori, I.; Iwasaki, G.; Scheidegger, A.; Koizumi, S.; Hayakawa, K.;
Mano, J. Preparation of Triazolyalkylphosphonates as Herbicides and Fungicides. PCT Int. Appl. WO 92-JP485
920417; Chem. Abstr. 1993, 118, 124547. (b) Isomura, Y.; Sakamoto, S.; Abe, T. Preparation of
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