Synthesis of brominated allenic, 1-3-butadienyl, and cyclobutenyl diphenylphosphine oxides

Full text of DOI:10.1134/S1070363212120195

ISSN 1070-3632, Russian Journal of General Chemistry, 2012, Vol. 82, No. 12, pp. 2009–2010. © Pleiades Publishing, Ltd., 2012.
Original Russian Text © A.S. Bogachenkov, B.I. Ionin, 2012, published in Zhurnal Obshchei Khimii, 2012, Vol. 82, No. 12, pp. 2056–2058.
LETTERS
TO THE EDITOR
Synthesis of Brominated Allenic, 1-3-Butadienyl,
and Cyclobutenyl Diphenylphosphine Oxides
A. S. Bogachenkov and B. I. Ionin
St. Petersburg State Institute of Technology, Moskovskii pr. 26, St. Petersburg, 190013 Russia
e-mail: borisionin@mail.ru
Received October 22, 2012
DOI: 10.1134/S1070363212120195
It is known that the halogenation of allenic phos-
phine oxides leads to the formation of stable phos-
pholene salts [1, 2]. Allenic phosphine oxides are
intermediates in the synthesis of cyclobutenyl
phosphine oxides [3]. In this work we found that the
reaction of the brominated allenic diphenylphosphine
oxide I, II with bromine occurs via the intermediate
formation of unstable phospholene salts. The latter
easily eliminate hydrogen bromide to afford 1,2-
dibromo-3-tert-butyl(phenyl)-1,3-butadien-1-yldiphenyl-
phosphine oxides III, IV, which isomerized into the
corresponding cyclobutenes V, VI when refluxed in
toluene. These compounds contain the bromine atoms
both at the double bond and at the saturated carbon
atom. Therefore they are of interest to study further
transformations of cyclobutene carbocycles.
reduced pressure. The residue, yellow oil, was chro-
matographed on a silica gel column eluting with a
dichloromethane–methanol mixture (from 99:1 to 97:3).
The target dienes III, IV were recrystallized from
diethyl ether. The latter quantitatively isomerized into
cyclobutenes V, VI under reflux for 30 min in toluene.
All the obtained phosphine oxides are colorless
crystalline substances with the melting points above
100°C. Compound III, whose melting starts at 98.5°C,
is gradually transformed into a cyclic isomer V. This
fact was confirmed by the thin layer chromatography.
The structure of compounds obtained was proved
by the 13C, 1H, 31P NMR spectra.
The results of studying the reactions of dienes and
brominated cyclobutenyl phosphine oxides will be
published later. In particular, we found that these
compounds can be used for the synthesis of the
phosphorus-containing heterocyclic structures.
Allenes I, II were prepared by addition of diphenyl-
chlorophosphine to a cooled (–10°C) mixture of the
corresponding γ-bromopropargyl alcohol and triethyl-
amine in dichloromethane [2]. The product was isolated
by the recrystallization from diethyl ether. Then,
according to the procedure [2], to a solution of the
allene in dichloromethane cooled to 0°C was slowly
added a solution of the equivalent amount of bromine
in dichloromethane, maintaining the temperature between
0–4°C. The temperature was gradually raised to room
temperature, and the solvent was removed under a
1
The 13C, H, 31P NMR spectra were registered on a
Bruker Avance instrument operating at 400.13 (1H),
100.61 (13C), 161.98 MHz (31P) with internal reference
TMS or external 85% phosphoric acid in D2O. CDCl3
was used as a solvent. The melting points were measured
on a Koeffler heating block (VEB Wägetechnik
Rapido, PHMK 81/2969). The column chromato-
graphy was performed on a Merck Silica Gel 60 (40–
Br
R
Br
Br
Br
Br
R
Br
R
R
Br2
Δ
PPh2Cl
OH
Et3N
Ph
Ph
R
P+
Br
_HBr
Br
PhMe
CH2Cl2
O
PPh2
I, II
PPh2
III, IV
Br_
PPh2
O
O
O
V, VI
R = t-Bu (I, III, V); Ph (II, IV, VI).
2009

2010
BOGACHENKOV, IONIN
1,2-Dibromo-3-phenyl-1-diphenylphosphoryl-1,2-
63 mesh). The Rf values were determined in a di-
pentadiene (IV). Yield 79%, mp 138–139.5°С, Rf
0.54. Н NMR spectrum, δ, ppm (J, Hz): 5.33 s (1Н,
chloromethane–methanol system (98:2).
1
1-Bromo-3,4,4-trimethyl-1-diphenylphosphoryl-
=CH2), 5.51 s (1Н, =CH2), 7.30–7.34 m [3H, 1 p-H,
2 m-H, C(Ph)], 7.36–7.44 m [6Н, 2 o-H, C(Ph); 4 m-H,
P(Ph)], 7.49–7.53 m [2H, 2 p-H, P(Ph)], 7.76 d.d (4H,
4 o-H, P(Ph), 3JHH 7.9, 3JHP 11.9). 13С NMR spectrum,
δС, ppm (J, Hz): 118.41 (=СH2), 122.06 d [=С(Br)P,
1JСP 87.5], 126.78 [2 о-С, Ph(C)], 128.35 [2 m-С, p-С,
1,2-pentadiene (I). Yield 60%, mp 119–120°С, Rf
1
0.41. Н NMR spectrum, δ, ppm (J, Hz): 0.81 s [9H,
С(CH3)3], 1.67 d (=CCH3), 7.43–7.56 m (6H, 2 p-H,
3
3
4 m-H), 7.75 d.d (2H, 2 о-H, JHH 7.0, JHP 12.3), 7.79
3
3
d.d (2H, 2 о-H, JHH 7.2, JHP 12.2). 13С NMR spec-
4
trum, δС, ppm (J, Hz): 14.24 d (=СCH3, JСP 4.0),
3
Ph(C)], 128.42 d [4 m-С, Ph(P), JСP 15.1], 129.78 d
4
1
28.20 [С(СH3)3], 34.37 d [С(СH3)3, JСP 3.4], 81.85 d
[ipso-С, Ph(P), JСP 105.6], 131.57 d [ipso-С, Ph(P),
(=СBr, 1JСP 119.2), 120.64 d (=СCH3, 3JСP 9.4), 128.39
2
1JСP 105.6], 132.09 d [4 о-С, Ph(P), JСP 10.1], 132.31
3
3
d (2 m-С, JСP 12.8), 128.44 d (2 m-С, JСP 12.1),
[2 p-С, Ph(P)], 135.94 [ipso-С, Ph(C)], 143.28 d
1
1
2
[C=C(Br)P, JСP 16.1], 146.49 (С=СH2). 31Р NMR
130.20 d (ipso-С, JСP 111.1), 131.00 d (ipso-С, JСP
2
111.1), 131.74 d (2 о-С, JСP 10.1), 132.00 d (2 о-С,
spectrum: δР 26.5 ppm.
2JСP 9.4 Hz), 132.21 s (2 p-С), 205.04 d (=С=, JСP
2
1,2-Dibromo-3-tert-butyl-1-diphenylphosphoryl-
cyclobut-2-ene (V). Yield 98%, mp 184.5–186°С, Rf
13.5). 31Р NMR spectrum: δР 26.5 ppm.
1
1-Bromo-3-phenyl-1-diphenylphosphoryl-1,2-penta-
diene (II). Yield 56%, mp 132–133°С, Rf 0.40. Н
NMR spectrum, δ, ppm (J, Hz): 2.01 d (=CCH3), 7.23
d.d [2H, 2 o-H, C(Ph), 3JHH 6.8, 4JHH 1.5], 7.29–7.36 m
[3H, 1 p-H, 2 m-H, C(Ph)], 7.37–7.55 m [6H, 2 p-H,
0.38. Н NMR spectrum, δ, ppm (J, Hz): 0.90 s [9H,
1
2
3
С(CH3)3], 3.03 d.d (1Н, PCCH2, JHH 12.3, JHP 2.3),
3.32 d.d (1Н, PCCH2, 2JHH 12.3, 3JHP 5.0), 7.43–7.61 m
(6H, 2 p-H, 4 m-H), 7.93 d.d (2H, 2 o-H, 3JHH 7.3, 3JHP
10.3), 7.97 d.d (2H, 2 o-H, 3JHH 7.2, 3JHP 11.2). 13СNMR spec-
trum, δС, ppm (J, Hz): 26.98 [С(СH3)3], 33.76 [С(СH3)3],
3
4 m-H, P(Ph)], 7.76 d.d [2H, 2 o-H, P(Ph), JHH 7.1,
1
3JHP 12.3], 7.78 d.d [2H, 2 o-H, P(Ph), JHH 7.2, JHP
3
3
43.80 (СH2), 57.35 d [С(Br)P, JСP 72.4], 108.35 d
3
3
12.2]. 13С NMR spectrum, δС, ppm (J, Hz): 16.06 d
[=СС(СH3)3, JСP 5.0], 128.25 d (2 m-С, JСP 12.1),
128.31 d (2 m-С, 3JС1P 12.1), 128.67 d (ipso-С, 1JСP 103.6),
4
1
(=СCH3, JСP 4.0), 83.35 d (=СBr, JСP 114.4), 111.71
2
3
129.91 d (ipso-С, JСP 103.6), 132.47 d (2 о-С, JСP
d (=СCH3, JСP 10.1), 126.58 s [2 о-С, Ph(C)], 128.42
9.1), 132.56 (2 p-С), 132.64 d (2 о-С, 2JСP 9.1), 158.00
d [=CBr, 2JСP 11.1]. 31Р NMR spectrum: δР 31.5 ppm.
3
d [2 m-С, Ph(P), JСP 12.1], 128.49 d [2 m-С, Ph(P),
3JСP 12.1], 128.69 s [2 m-С, Ph(C)], 128.91 [p-С,
1
Ph(C)], 130.21 d [ipso-С, Ph(P), JСP 110.4], 130.34 d
1,2-Dibromo-3-phenyl-1-diphenylphosphoryl-
cyclobut-2-ene (VI). Yield 96%, mp 140–141°С, Rf
0.45. 1Н NMR spectrum, δ, ppm (J, Hz): 3.39 d.d (1Н,
1
[ipso-С, Ph(P), JСP 110.4], 131.74 d [2 о-С, Ph(P),
2JСP 9.4 Hz], 131.81 d [2 о-С, Ph(P), JСP 9.4 Hz],
2
132.35 d [2 п-С, Ph(P), 4JСP 1.7 Hz], 133.22 d [ipso-С,
2
3
PCCH2, JHH 11.7, JHP 1.0), 3.88 d.d (1Н, PCCH2,
2JHH 11.7, 3JHP 4.9), 7.35–7.60 m [5H, C(Ph); 6H, 2 p-H,
Ph(С), JСP 4.7], 208.12 d (=С=, JСP 13.2). 31Р NMR
4
2
3
3
4 m-H, P(Ph)], 7.94 d.d (2H, 2 o-H, JHH 8.0, JHP
spectrum: δР 25.9 ppm.
11.0), 8.08 d.d (2H, 2 o-H, JHH 8.5, JHP 10.4). 13С
3
3
1,2-Dibromo-3-tert-butyl-1-diphenylphosphoryl-
1,2-pentadiene (III). Yield 85%, Rf 0.63. Н NMR
NMR spectrum, δС, ppm (J, Hz): 44.03 (CH2), 58.09 d
1
1
3
[С(Br)P, JСP 72.7], 110.00 d (=СPh, JСP 6.0), 126.49
spectrum, δ, ppm (J, Hz): 1.37 s [9H, С(CH3)3], 4.99 s
(1Н, =CH2), 5.15 s (1Н, =CH2), 7.41–7.46 m (2H, 2 m-
H), 7.50–7.55 m (3Н, 1 p-H, 2 m-H), 7.58–7.63 m (1H,
3
[2 о-С, Ph(C)], 128.21 d [2 m-С, Ph(P), JСP 13.1],
3
128.37 d [2 m-С, Ph(P), JСP 12.1], 128.50 [2 m-С,
p-С, Ph(C)], 129.08 [ipso-С, Ph(P), 1JСP 104.6], 130.26
3
3
1 p-H), 7.662 d.d (1H, 1 o-H, JHH 8.3, JHP 12.5),
1
[ipso-С, Ph(P), JСP 104.6], 132.35 d [2 о-С, Ph(P),
3
3
7.665 d.d (1H, 1 o-H, JHH 8.3, JHP 12.6), 7.879 d.d
2JСP 10.1], 132.63 [2 p-С, Ph(P)], 133.25 d [2 о-С,
3
(1H, 1 o-H, 3JHH 8.1, JHP 12.3), 7.882 d.d (1H, 1 o-H,
2
Ph(P), JСP 10.1], 138.84 [ipso-С, Ph(C)], 145.64 d
3
3JHH 8.2, JHP 12.4). 13С NMR spectrum, δС, ppm
[=CBr, 2JСP 12.1]. 31Р NMR spectrum: δР 30.0 ppm.
(J, Hz): 30.92 [С(СH3)3], 35.54 [С(СH3)3], 117.59
(=СH2), 121.66 d [=С(Br)P, 1JСP 88.9], 128.16 d (2 m-
REFERENCES
3
3
1. Angelov, Kh.M., Doctorate (Chem.) Dissertation,
Leningrad, 1986.
2. Saalfrank, R.W., Welch, A., Haubner, M., and Bauer, U.,
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С, JСP 12.8), 128.62 d (2 m-С, JСP 12.1), 130.73 d
1
1
(ipso-С, JСP 109.7), 131.20 d (ipso-С, JСP 109.7),
132.06 d (2 о-С, 2JСP 10.8), 132.27 d (2 о-С, 2JСP 11.4),
132.42 (2 p-С), 145.58 d [C=C(Br)P, 2JСP 14.8], 157.24
d (С=СH2, 3JСP 2.0). 31Р NMR spectrum: δР 26.9 ppm.
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 82 No. 12 2012