S.R. Kolla, Y.R. Lee / Tetrahedron 68 (2012) 226e237
233
of the reaction, the mixture was evaporated under reduced pres-
sure and crude product was purified by column chromatography on
silica gel using hexane/ethylacetate (3:2) gave product 4b (261 mg,
of the reaction the mixture was evaporated under reduced pressure
and crude product was purified by column chromatography on
silica gel using hexane/ethylacetate (1:1) gave product 4e (232 mg,
85%) as
a
solid: mp 56e57 ꢀC; 1H NMR (300 MHz, CDCl3)
72%) as
a
solid: mp 57e58 ꢀC; 1H NMR (300 MHz, CDCl3)
3
3
d
7.13e6.99 (m, 4H), 4.27 (t, 1H, JHH¼8.7 Hz), 3.99e3.87 (m, 2H),
d
7.39e7.37 (m, 2H), 6.93 (d, 2H, JHH¼8.7 Hz), 4.43 (dd, 1H,
3.85e3.72 (m,1H), 3.60e3.46 (m,1H), 3.32 (dd,1H, 3JHH¼8.4 Hz and
3JHH¼8.1 Hz and JHP¼8.7 Hz), 4.20e4.09 (m, 2H), 4.03e3.93 (m,
3
2JHP¼21.0 Hz), 2.17 (s, 3H), 1.14 (t, 3H, JHH¼7.2 Hz), 0.90 (t, 3H,
1H), 3.80 (s, 3H), 3.75e3.70 (m, 1H), 3.51 (dd, 1H, JHH¼7.8 Hz and
3
3
3JHH¼6.9 Hz); 13C NMR (75 MHz)
d
139.2, 130.3, 130.0, 129.9, 129.2,
2JHP¼21.3 Hz), 1.33 (t, 3H, 3JHH¼7.2 Hz), 1.13 (t, 3H, 3JHH¼6.9 Hz); 13
C
3
3
126.2, 111.6 (d, JCP¼7.7 Hz), 111.5 (d, JCP¼13.1 Hz), 64.3 (d,
NMR (75 MHz)
d
160.2,130.5 (d, 3JCP¼6.0 Hz),122.0 (d, 3JCP¼5.4 Hz),
2JCP¼7.1 Hz), 63.4 (d, 2JCP¼7.1 Hz), 44.5 (d, 1JCP¼142.8 Hz), 25.5, 21.4,
114.6, 111.6 (d, JCP¼11.0 Hz), 111.5 (d, JCP¼12.6 Hz), 64.1 (d,
3
3
3
3
16.2 (d, JCP¼5.5 Hz), 16.1 (d, JCP¼5.5 Hz); IR (KBr) 2979, 2906,
2609, 2480, 2257, 1605, 1466, 1387, 1241, 1026 cmꢁ1; MS (m/z, EI)
306 (Mþ, 35), 169 (22), 168 (34), 143 (100), 140 (17), 138 (64), 115
(16), 111 (37), 109 (21), 105 (23), 81 (12).
2JCP¼7.1 Hz), 63.1 (d, 2JCP¼7.7 Hz), 55.1, 43.4 (d, 1JCP¼143.9 Hz), 25.6,
3
16.0 (t, JCP¼6.0 Hz); IR (KBr) 2987, 2857, 2607, 2507, 2374, 2256,
1611, 1512, 1248, 1026 cmꢁ1; MS (m/z, EI) 322 (Mþ, 28), 258 (13),
257 (100), 185 (27), 159 (20), 121 (97), 111 (8).
3.6. Diethyl 2,2-dicyano-1-p-tolylethylphosphonate (4c)7c,12
3.9. Diethyl 2,2-dicyano-1-(2,5-dimethylphenyl)
ethylphosphonate (4f)
A mixture of p-tolualdehyde (1c) (120 mg, 1.0 mmol), malononi-
trile (2a) (66 mg, 1.0 mmol) and triethyl phosphite (3a) (166 mg,
1.0 mmol) in ethanol (5 mL) in the presence of 20 mol % of EDDA
(36 mg) was stirred at room temperature for 5 h. After completion of
the reaction the mixture was evaporated under reduced pressure and
crude product was purified by column chromatography on silica gel
using hexane/ethylacetate (7:3) gave product 4c (230 mg, 75%) as
A
mixture of 2,5-dimethlybenzaldehyde (1f) (134 mg,
1.0 mmol), malononitrile (2a) (66 mg, 1.0 mmol), and triethyl
phosphite (3a) (166 mg, 1.0 mmol) in ethanol (5 mL) in the pres-
ence of 20 mol % of EDDA (36 mg) was stirred at room temperature
for 2 h. After completion of the reaction the mixture was evapo-
rated under reduced pressure and crude product was purified by
column chromatography on silica gel using hexane/ethylacetate
(3:2) gave product 4f (282 mg, 88%) as a solid: mp: 73e75 ꢀC; 1H
a solid: mp 88e90 ꢀC; 1H NMR (300 MHz, CDCl3)
d 7.27 (d, 2H,
3
J¼6.6 Hz), 7.15 (d, 2H, J¼6.6 Hz), 4.40 (dd, 1H, JHH¼8.1 Hz and
3JHP¼9.0 Hz), 4.16e4.06 (m, 2H), 3.97e3.90 (m, 1H), 3.73e3.68 (m,
1H), 3.46 (dd, 1H, 3JHH¼8.1 Hz and 2JHP¼21.3 Hz), 2.29 (s, 3H), 1.27 (t,
NMR (300 MHz, CDCl3)
d
7.30 (s, 1H), 7.11 (d, 1H, 3JHH¼7.8 Hz), 7.04
3
3
(d, 1H, JHH¼7.8 Hz), 4.48 (t, 1H, JHH¼9.3 Hz), 4.21e4.02 (m, 2H),
3.95e3.81 (m, 2H), 3.61e3.48 (m, 1H), 2.33 (s, 3H), 2.30 (s, 3H), 1.34
3H, 3JHH¼6.9 Hz),1.06 (t, 3H, 3JHH¼7.2 Hz); 13C NMR (75 MHz)
d 139.2,
3
3
3
3
130.1, 129.2 (d, JCP¼6.0 Hz), 127.2 (d, JCP¼6.0 Hz), 111.6 (d,
(t, 3H, JHH¼7.2 Hz), 1.00 (t, 3H, JHH¼6.9 Hz); 13C NMR (75 MHz,
3
2
3
3JCP¼11.0 Hz), 111.4 (d, JCP¼12.6 Hz), 64.3 (d, JCP¼7.1 Hz), 63.3 (d,
2JCP¼7.2 Hz), 44.2 (d, 1JCP¼143.4 Hz), 25.6, 21.2, 16.2 (d, 3JCP¼6.0 Hz),
16.1 (d, 3JCP¼6.1 Hz);IR(KBr)2989,2858, 2608, 2507, 2375, 2255,1515,
1450, 1387, 1238, 1024 cmꢁ1; MS (m/z, EI) 306 (Mþ, 31), 241 (21), 169
(18), 143 (100), 138 (37), 115 (13), 111 (17), 109 (15), 105 (44), 81 (10).
CDCl3)
d
136.8, 134.4 (d, JCP¼7.7 Hz), 131.4, 130.2, 128.8 (d,
3JCP¼6.0 Hz),128.1,111.6 (d, 3JCP¼6.6 Hz),111.4, 64.5 (d, 2JCP¼7.2 Hz),
63.3 (d, 2JCP¼7.1 Hz), 39.7 (d, 1JCP¼143.9 Hz), 25.3, 21.2, 19.6, 16.3 (d,
3JCP¼6.0 Hz), 16.1 (d, 3JCP¼5.4 Hz); IR (KBr) 2981, 2871, 2609, 2359,
2258, 1690, 1455, 1242, 1041 cmꢁ1; HRMS m/z (Mþ) calcd for
C16H21N2O3P: 320.1290; found: 320.1288.
3.7. Diethyl 2,2-dicyano-1-(3-methoxyphenyl)
ethylphosphonate (4d)12
3.10. Diethyl 2,2-dicyano-1-(2,5-dimethoxyphenyl)
ethylphosphonate (4g)
A mixture of m-anisaldehyde (1d) (136 mg, 1.0 mmol), malo-
nonitrile (2a) (66 mg, 1.0 mmol), and triethyl phosphite (3a)
(166 mg, 1.0 mmol) in ethanol (5 mL) in the presence of 20 mol % of
EDDA (36 mg) was stirred at room temperature for 4 h. After
completion of the reaction the mixture was evaporated under re-
duced pressure and crude product was purified by column chro-
matography on silica gel using hexane/ethylacetate (3:2) gave
product 4d (290 mg, 90%) as an oil: 1H NMR (300 MHz, CDCl3)
A
mixture of 2,5-dimethoxybenzaldehyde (1g) (166 mg,
1.0 mmol), malononitrile (2a) (66 mg, 1.0 mmol), and triethyl
phosphite (3a) (166 mg, 1.0 mmol) in ethanol (5 mL) in the pres-
ence of 20 mol % of EDDA (36 mg) was stirred at room temperature
for 3 h. After completion of the reaction, the mixture was evapo-
rated under reduced pressure and crude product was purified by
column chromatography on silica gel using hexane/ethylacetate
3
3
d
7.24 (t, 1H, JHH¼7.8 Hz), 6.98 (s, 2H), 6.85 (d, 1H, JHH¼8.1 Hz),
(3:2) gave product 4g (265 mg, 75%) as an oil: 1H NMR (300 MHz,
CDCl3)
3
3
4.67 (t, 1H, JHH¼8.7 Hz), 4.10e4.05 (m, 2H), 3.99e3.90 (m, 1H),
d
7.10 (s, 1H), 6.82 (br s, 2H), 4.55 (t, 1H, JHH¼9.0 Hz), 4.26
3.77e3.71 (m, 4H), 3.58 (dd, 1H, 3JHH¼7.8 Hz and 2JHP¼21.3 Hz),1.25
(dd, 1H, JHH¼8.1 Hz and JHP¼21.0 Hz), 4.16e3.92 (m, 4H), 3.76 (s,
3
2
(t, 3H, JHH¼6.6 Hz), 1.05 (t, 3H, JHH¼6.9 Hz); 13C NMR (75 MHz)
3H), 3.70 (s, 3H), 1.27 (t, 3H, 3JHH¼6.9 Hz), 1.09 (t, 3H, 3JHH¼6.9 Hz);
3
3
3
3
3
d
159.9, 131.7 (d, JCP¼6.0 Hz), 130.2, 121.4 (d, JCP¼6.0 Hz), 114.9,
13C NMR (75 MHz)
d
153.7, 151.5 (d, JCP¼7.1 Hz), 119.6 (d,
3
3
3
114.8, 111.6 (d, JCP¼4.9 Hz), 111.5 (d, JCP¼7.2 Hz), 64.2 (d,
3JCP¼5.4 Hz), 115.6, 115.2 (d, JCP¼4.4 Hz), 112.6, 111.7 (d,
2JCP¼6.6 Hz), 63.2 (d, JCP¼7.1 Hz), 55.2, 44.0 (d, JCP¼142.8 Hz),
3JCP¼6.6 Hz), 111.5 (d, JCP¼11.0 Hz), 64.0 (d, JCP¼6.6 Hz), 63.2 (d,
2
1
3
2
3
3
1
25.3, 16.0 (d, JCP¼6.0 Hz), 15.9 (d, JCP¼6.0 Hz); IR (neat) 2980,
2920, 2597, 2257, 1597, 1471, 1249, 1164, 1031 cmꢁ1; MS (m/z, EI)
322 (Mþ, 80), 229 (25), 185 (36), 159 (96), 138 (100), 121 (45), 111
(61), 110 (21), 109 (28), 81 (21).
2JCP¼7.1 Hz), 56.4, 55.7, 36.6 (d, JCP¼145.5 Hz), 24.9, 16.2 (d,
3JCP¼6.0 Hz), 16.1 (d, 3JCP¼6.0 Hz); IR (neat) 2977, 2257, 1616, 1496,
1240, 1034 cmꢁ1; HRMS m/z (Mþ) calcd for C16H21N2O5P: 352.1188;
found: 352.1188.
3.8. Diethyl 2,2-dicyano-1-(4-methoxyphenyl)
ethylphosphonate (4e)7c,12
3.11. Diethyl 2,2-dicyano-1-(4-fluorophenyl)
ethylphosphonate (4h)
A mixture of p-anisaldehyde (1e) (136 mg, 1.0 mmol), malono-
nitrile (2a) (66 mg, 1.0 mmol), and triethyl phosphite (3a) (166 mg,
1.0 mmol) in ethanol (5 mL) in the presence of 20 mol % of EDDA
(36 mg) was stirred at room temperature for 3 h. After completion
A mixture of 4-fluorobenzaldehyde (1h) (124 mg, 1.0 mmol),
malononitrile (2a) (66 mg, 1.0 mmol), and triethyl phosphite (3a)
(166 mg, 1.0 mmol) in ethanol (5 mL) in the presence of 20 mol % of
EDDA (36 mg) was stirred at room temperature for 2 h. After