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F. Moreau et al. / Tetrahedron 56 (2000) 285–293
dropwise, 4-FPTCl (5 g, 26 mmol) dissolved in anhydrous
CH2Cl2 (100 mL). After 30 min stirring at Ϫ30ЊC, solvents
were evaporated under vacuum and the residue purified on a
flash silica gel column (C6H12:CH3COOC2H5 1:0 to 1:1 and
then ethanol) the FTP derivative was obtained as a white
solid (8.03 g, 49%) which crystallized from CH2Cl2. mp:
J6.1 Hz, CH3); 2.43–2.54 (m, 2H, CH2CN); 3.58–3.68
(m, 2H, 2CHN); 4.12: 4.24; 4.88; 4.91 (4d, 4H,
JGem15.2 Hz, 2NCHHPh); 7.29–7.40 (m, 10H, arom.).
13C NMR: d 12.57 (CH3); 16.50 (CH2CN); 45.27; 45.88
(2NCH2Ph); 51.18; 53.10 (2CHN); 116.92 (CN); 127.51;
128.81; 136.57; 136.75 (arom.); 159.87 (CyO). Anal.
calcd for C20H21N3O: C, 75.21; H, 6.63; N, 13.15. Found:
C, 75.04; H, 6.68; N, 13.18.
1
104–106ЊC H NMR: d 2.51 (s, 1H, OH); 3.59–3.63 (m,
1H, J9.1 Hz, CHN): 3.76–3.84 (2dd, 2H, JGem12.7 Hz,
J2.5 Hz, J5.1 Hz, CHHOH); 3.87–3.92 (m, 1H, CHN);
4.77; 4.91 (2dd, 2H, JGem11.7 Hz, J6.1 Hz, J4.6 Hz,
CHHOCS); 4.30; 4.31; 4.80; 4.96 (4d, 4H, JGem15.7 Hz,
2NCHHPh); 7.01–7.05 (m, 2H, 2CHCO); 7.08–7.14 (m,
2H, 2CHCF); 7.28–7.40 (m, 10H, 2NCH2Ph). 13C
NMR: d 46.10 and 46.57 (2NCH2Ph); 53.68 (CHN);
56.31 (CHN); 56.80 (CH2OH); 71.60 (CH2OCS);
The cyano derivative (1.15 g, 3.60 mmol) was dissolved in
anhydrous toluene (15 mL) and at Ϫ70ЊC, 1.5 M diisobutyl-
aluminium hydride (DIBAH) in toluene (6 mL, 9 mmol)
was added. After 30 min stirring at Ϫ70ЊC, the mixture
was hydrolyzed by 1N HCl (0.5 mL) and was allowed to
warm to room temperature, then 1N HCl (75 mL) was
added. The product was extracted with CH2Cl2. The organic
phase was washed with brine, dried and evaporated under
vacuum. Purification performed on a flash silica gel column
(C6H12:CH3COOC2H5, 7:3 to 1:1) yielded 13 as a colorless
2
3
116.28 (d, JC–F22.4 Hz, CCF); 123.29 (d, JC–F
8 Hz, CCCF); 127.51–128.77; 136.96; 137.19
(2CH2Ph); 149.09 (O–C arom.); 160.66 (d,
JC–F246.2 Hz, C–F); 161.00 (CyO); 194.54 (CyS).
Anal. calcd for C26H25FN2O4S: C, 64.99; H, 5.24; N,
5.83. Found: C, 64.85; H, 5.32; N, 5.77.
1
oil (800 mg, 70%). H NMR: d 1.00 (d, 3H, J6.6 Hz,
CH3); 2,64 (ddd, 1H, J8.2 Hz, JGem18.3 Hz, J0.6 Hz,
CHHCHO); 2.70 (ddd, 1H, J5.1 Hz, J18.3 Hz,
JGem0.6 Hz, CHHCHO); 3.64 (dq, 1H, J7.6 Hz,
J6.6 Hz, CHN); 3.88–3.94 (m, 1H, CHN); 4.05; 4.23;
4.71; 4.91 (4d, 4H, JGem15.2, 2NCHHPh); 7.27–7.37 (m,
10H, arom.); 9.66 (s, 1H, CHO). 13C NMR: d 12.61 (CH3);
42.17 (CH2CHO); 45.12; 46.00 (2NCH2Ph); 51.03 (CHN);
52.13 (CHN); 127.35–128.62; 137.18; 137.27 (arom.);
160.33 (CyO); 199.42 (CHO).
FTP derivative (4.21 g, 8.77 mmol), AIBN (720 mg,
4.38 mmol) and freshly distilled Bu3SnH (3.77 mL,
14 mmol) were dissolved in anhydrous toluene (150 mL).
Argon was bubbled in the mixture during 45 min. After
heating with reflux for 1 h with continuous bubbling of
argon, toluene was evaporated under vacuum and the
residue was purified on flash silica gel column
(C6H12:CH3COOC2H5 1:0 to 4:6). 12 (1.51 g, 57%) was
obtained as a colorless oil. 1H NMR: d(1.21 (d, 3H,
J6.6 Hz, CH3); 2.02 (s, 1H, OH); 3.39–3.43 (m, 1H,
CHN); 3.55–3.62 (m, 1H, J8.7 Hz, CHN); 3.69; 3.74
(2dd, 2 H, JGem12.2 Hz, J4.1 Hz, J5.1 Hz, CHHOH);
4.09; 4.30; 4.78; 4.86 (4d, 4H, JGem15.2 Hz, 2NCHHPh);
7.27–7.37 (m, 10H, arom.). 13C NMR: d 12.70 (CH3); 45–
25; 46.30 (2NCH2Ph); 51.02 (CHN); 57.34 (CHN); 59.39
(CH2OH); 127.31; 127.43; 127.84; 128.00; 128.52; 128.64;
137.28; 137.84 (arom.); 161.12 (CyO). Anal. calcd
C19H22N2O2: C, 73.52; H, 7.14; N, 9.02. Found: C, 73.44;
H, 7.19; N, 9.07.
cis-1,3-Dibenzyl-4-formyl-5-methyl imidazolidin-2-one 14.
DMSO (273 mL, 385 mmol) was dissolved in anhydrous
CH2Cl2 (10 mL) at Ϫ78ЊC and oxalylchloride (169 mL,
1.93 mmol) was added dropwise. After 10 min stirring at
Ϫ78ЊC, 12 (500 mg, 1.61 mmol) in CH2Cl2 (5 mL) was
added slowly. The mixture was stirred 30 min, then NEt3
(673 mL, 4.84 mmol) was added and after 40 min stirring at
Ϫ78ЊC, H2O (2 mL). The mixture was extracted with
CH2Cl2 ꢀ4×15 mL: The organic phase was washed with
brine, dried, evaporated under vacuum. The crude aldehyde
14 was obtained as a colorless oil (496 mg) and was not
1
purified. H NMR: d 1.15 (d, 3H, J6.1 Hz, CH3); 3.70–
cis-1,3-Dibenzyl-5-methyl-4-(2-oxyethyl) imidazolidin-2-
one 13. 12 (1.97 g, 6.35 mmol) was dissolved into anhy-
drous CH2Cl2 (20 mL), mesyl chloride (0.64 g, 8.2 mmol)
and NEt3 (1.32 mL; 9.52 mmol) were added. After stirring
15 min at room temperature, 1N HCl (10 mL) was added,
the product was extracted with CH2Cl2. The organic phase
was washed with brine, dried (MgSO4) and evaporated.
Purification was performed on a flash silica gel column
(C6H12:CH3COOC2H5, 7:3 to 1:1) giving the mesylate
3.77 (m, 2H, J9.1 Hz, 2CHN); 4.11; 4.31; 4.82; 4.88 (4d,
4H JGem15.2 Hz, 2NCHHPh); 7.26–7.37 (m, 10, arom.);
9.51 (d, 1H, J4.1 Hz, CHO). 13C NMR: d 14.07 (CH3);
45.47; 47.09 (2NCH2Ph); 50.87; 64.20 (2CHN); 127.57–
128.75; 136.37; 136.47 (arom.); 160.15 (CyO); 200.59
(CHO).
cis-4-[(Z and E)-5-Hydroxypent-1-enyl]-5-methyl imida-
zolidin-2-one 7a, 7b. 1.6N n-butyllithium in hexane
(5.63 mL, 9 mmol) was added at 0ЊC to a solution of
Ph3Pϩ (CH2)4OBn, BrϪ15 (4.8 g, 9.75 mmol, dried for
30 min at 80ЊC under vacuum) in anhydrous THF
(15 mL). The brick red solution was stirred 10 min at 0ЊC
and cooled at Ϫ60ЊC. 14 (2 g, 6.5 mmol) dissolved in anhy-
drous THF (15 mL) was then added, followed after 25 min
stirring by 1.6N n-butyllithium (4.38 mL, 7 mmol). The
mixture was allowed to warm to Ϫ30ЊC, kept at Ϫ30ЊC
for 30 min and then cooled at Ϫ60ЊC, treated with absolute
ethanol (550 mL, 9.5 mmol) with strong agitation, then
warmed to room temperature. t-BuOK (1.43 g, 12.7 mmol)
was added and after 2 h stirring at room temperature,
(2 g, 80%) as
a
white solid recrystallized from
CH2Cl2:C5H12, mp: 124–126ЊC. To a solution of the
mesylate (1.74 g, 4.48 mmol) in anhydrous DMSO
(10 mL) was added KCN (583 mg, 8.96 mmol). After heat-
ing at 70ЊC during 20 h, DMSO was evaporated under
vacuum at 50ЊC. The crude product was dissolved in
CH2Cl2 (300 mL) and CH2Cl2 was washed successively
with water (15 mL) and brine (15 mL) then dried and evapo-
rated under vacuum. Purification on a flash silica gel column
(C6H12:CH3COOC2H5, 8:2 to 1:1) yielded the cyano deriva-
tive as a white solid (1.28 g, 80%) recrystallized from
1
CH2Cl2:C5H12. mp 125–127ЊC. H NMR: d 1.24 (d, 3H,