10244
H. Nagura et al. / Tetrahedron 63 (2007) 10237–10245
4.19. 4-[Difluoro-(3-tetrahydrofuryl)methyl]-1,3-dioxo-
lan-2-one (15) (diastereomeric mixture)
NMR d ꢁ35.48- ꢁ37.81 (m, 2F). FAB-MS (m/z) 252
(M++H). HRFAB-MS m/z calcd for C11H20F2NO3:
252.1411. Found: 252.1407.
Oil; 1H NMR d 4.86–4.54 (m, 3H), 4.02–3.74 (m, 4H), 3.09–
2.83 (m, 1H), 2.20–1.89 (m, 2H). 19F NMR d ꢁ41.91 to
ꢁ44.34 (m, 2F). MS (m/z) 207 (M+ꢁH), 189 (M+ꢁF), 87
(M+ꢁF2C–C4H7O). HRFAB-MS m/z calcd for C8H10F2-
O4Na (M++Na): 231.0439. Found: 231.0441.
4.25. 5-[(Cyclohexyl)difluoromethyl]-3-methyloxazoli-
dinone (21)
Oil; 1H NMR d 4.73–4.59 (m, 1H), 3.74–3.58 (m, 2H), 2.91
(s, 3H), 2.14–1.62 (m, 6H), 1.33–1.13 (m, 5H). 13C NMR
d 156.69, 121.84 (dd, J¼250.1, 244.3 Hz), 69.41 (dd,
J¼39.17, 29.1 Hz), 45.79 (dd, J¼5.3, 3.4 Hz), 40.66 (t,
J¼21.8 Hz), 30.94, 29.77, 25.95 (dd, J¼6.1, 2.8 Hz),
25.84, 25.43, 24.06 (dd, J¼5.0, 3.9 Hz). 19F NMR
d ꢁ45.35 (ddd, 1F, J¼258.9, 20.3, 3.7 Hz), ꢁ46.72 (ddd,
1F, J¼258.9, 18.5, 9.2 Hz). MS (m/z) 233 (M+), 100.
HRMS m/z calcd for C11H17F2NO2: 233.1227. Found:
233.1222.
4.20. 4-[(3-tert-Butoxy-1,1-difluoro)propyl]-1,3-dioxo-
lan-2-one (16)
Oil; 1H NMR d 5.10–4.97 (m, 1H), 4.59–4.48 (m, 2H), 3.55
(t, 2H, J¼5.8 Hz), 2.44–2.09 (m, 2H), 1.19 (s, 9H). 13C
NMR d 153.82, 120.56 (dd, J¼247.0, 243.1 Hz), 74.89
(dd, J¼34.7, 26.3 Hz), 73.63, 64.26 (dd, J¼5.0, 2.8 Hz),
54.76 (t, J¼6.7 Hz), 34.54 (dd, J¼23.5, 22.9 Hz), 27.41.
19F NMR d ꢁ33.90 to ꢁ35.17 (m, 1F), ꢁ36.78 to ꢁ37.93
(m, 1F). FAB-MS (m/z) 239 (M++H). HRFAB-MS m/z calcd
for C10H17F2O4: 239.1095. Found: 239.1091.
4.26. 5-(1,1-Difluorooctyl)-3-methyloxazolidinone (22)
Oil; 1H NMR d 4.60–4.446 (m, 1H), 3.71–3.60 (m, 2H), 2.91
(s, 3H), 2.17–1.84 (m, 2H), 1.58–1.46 (m, 2H), 1.37–1.25
(m, 8H), 0.89 (t, 3H, J¼6.8 Hz). 13C NMR d 156.65,
121.36 (dd, J¼248.2, 239.8 Hz), 71.22 (dd, J¼40.2,
27.9 Hz), 45.81 (dd, J¼4.5, 3.4 Hz), 33.07 (dd, J¼23.5,
22.9 Hz), 31.67, 30.94, 29.25, 29.03, 22.65, 21.36 (dd,
J¼5.6, 2.8 Hz), 14.14. 19F NMR d ꢁ35.55 to ꢁ36.72 (m,
1F), ꢁ40.22 to ꢁ41.43 (m, 1F). MS (m/z) 249 (M+), 149,
100. HRMS m/z calcd for C12H21F2NO2: 249.1540. Found:
249.1539.
4.21. 4-[(Cyclohexyl)difluoromethyl]-1,3-dioxolan-2-one
(17)
Oil; 1H NMR d 4.92–4.78 (m, 1H), 4.69–4.50 (m, 2H), 2.01–
1.74 (m, 6H), 1.31–1.24 (m, 5H). 13C NMR d 153.61, 121.25
(dd, J¼249.8, 243.7 Hz), 72.36 (dd, J¼41.4, 28.5 Hz), 64.02
(dd, J¼5.6, 3.9 Hz), 40.80 (t, J¼21.8 Hz), 25.76 (dd, J¼5.6,
2.8 Hz), 25.69, 25.46 (d, J¼1.1 Hz), 25.29, 24.04 (dd,
J¼4.5, 3.9 Hz). 19F NMR d ꢁ54.11 (ddd, 1F, J¼303.3,
53.6, 3.7 Hz), ꢁ59.75 (ddd, 1F, J¼303.3, 55.5, 16.6 Hz).
FAB-MS (m/z) 221 (M++H). HRFAB-MS m/z calcd for
C10H15F2O3: 221.0989. Found: 221.0986.
4.27. 4-[Difluoro(phenyl)methyl]-1,3-dioxlan-2-one (23)
Oil; 1H NMR d 7.56–7.45 (m, 5H), 5.04–4.92 (m, 1H), 4.68–
4.43 (m, 2H). 13C NMR d 153.32, 131.36 (dd, J¼25.2,
24.6 Hz), 131.21 (dd, J¼2.2, 1.7 Hz), 128.83, 125.59 (t,
J¼6.1 Hz), 118.15 (dd, J¼249.3, 244.3 Hz), 75.88 (dd,
J¼39.7, 32.4 Hz), 64.21 (t, J¼3.3 Hz). 19F NMR d ꢁ30.95
(dd, 1F, J¼262.6, 5.5 Hz), ꢁ37.90 (dd, 1F, J¼262.6,
12.9 Hz). MS (m/z) 214 (M+), 127. HRMS m/z calcd for
C10H8F2O3: 214.0442. Found: 214.0443.
4.22. 4-(1,1-Difluorooctyl)-1,3-dioxolan-2-one (18)
Oil; 1H NMR d 4.80–4.51 (m, 3H), 2.18–1.81 (m, 2H), 1.60–
1.48 (m, 2H), 1.39–1.23 (m, 8H), 0.89 (t, 3H, J¼7.1 Hz). 13C
NMR d 153.49, 120.72 (dd, J¼249.3, 241.5 Hz), 74.16 (dd,
J¼40.8, 27.9 Hz), 63.96 (dd, J¼5.0, 3.4 Hz), 33.11 (dd,
J¼23.5, 22.4 Hz), 31.65, 29.18, 28.98, 22.65, 21.25
(dd, J¼5.6, 2.8 Hz), 14.41. 19F NMR d ꢁ35.57 to ꢁ36.76
(m, 1F), ꢁ40.22 to ꢁ41.43 (m, 1F). MS (m/z) 236 (M+),
149. HRMS m/z calcd for C11H18F2O3: 236.1224. Found:
236.1232.
4.28. 4-[Difluoro(2-furyl)methyl]-1,3-dioxolan-2-one
(24)
Oil; 1H NMR d 7.55–7.54 (m, 1H), 6.83–6.81 (m, 1H), 6.51–
6.50 (m, 1H), 5.23–5.11 (m, 1H), 4.72–4.56 (m, 2H). 13C
NMR d 153.24, 144.97 (dd, J¼2.2, 1.7 Hz), 143.58 (dd,
J¼37.4, 33.0 Hz), 113.82 (dd, J¼243.7, 240.3 Hz), 112.33
(dd, J¼3.4, 2.8 Hz), 111.00 (t, J¼1.1 Hz), 74.21 (dd,
J¼37.4, 29.6 Hz), 63.94 (t, J¼3.4 Hz). 19F NMR d ꢁ28.80
(dd, 1F, J¼280.0, 5.5 Hz), ꢁ38.17 (dd, 1F, J¼280.0,
11.1 Hz). MS (m/z) 204 (M+), 117. HRMS m/z calcd for
C8H6F2O4: 204.0234. Found: 204.0237.
4.23. 5-[Difluoro(3-tetrahydrofuryl)methyl]-3-methyl-
oxazolidinone (19) (1:1 diastereomeric mixture)
Oil; 1H NMR d 4.67–4.44 (m, 1H), 4.01–3.63 (m, 6H), 3.18–
2.92 (m, 4H), 2.22–1.87 (m, 2H). 19F NMR d ꢁ43.16 (ddd,
1F, J¼262.6, 18.5, 12.9 Hz), ꢁ44.43 (ddd, 1F, J¼262.4,
20.2, 3.7 Hz). MS (m/z) 222 (M++H). HRFAB-MS m/z calcd
for C9H14F2NO3: 222.0942. Found: 222.0945.
4.24. 5-[(3-tert-Butoxy-1,1-difluoro)propyl]-3-methylox-
azolidinone (20)
4.29. 5-[Difluoro(phenyl)methyl]-3-methyloxazolidi-
none (25)
Oil; 1H NMR d 4.81–4.67 (m, 1H), 3.64–3.54 (m, 4H), 2.90
(s, 3H), 2.44–2.06 (m, 2H), 1.19 (s, 9H). 13C NMR d 156.82,
121.00 (dd, J¼246.5, 244.3 Hz), 73.36, 71.69 (dd, J¼34.1,
30.2 Hz), 54.91 (dd, J¼6.7, 6.1 Hz), 46.10 (dd, J¼4.5,
3.4 Hz), 34.37 (dd, J¼23.5, 22.9 Hz), 30.95, 27.45. 19F
Oil; 1H NMR d 7.55–7.42 (m, 5H), 4.85–4.73 (m, 1H), 3.67
(d, 2H, J¼7.4 Hz), 2.82 (s, 3H). 13C NMR d 156.45, 132.20
(dd, J¼25.7, 25.2 Hz), 130.72 (t, J¼1.7 Hz), 128.51, 125.69
(t, J¼6.1 Hz), 118.65 (dd, J¼248.7, 244.3 Hz), 72.93 (dd,
J¼39.13, 32.42 Hz), 46.32 (t, J¼3.35 Hz), 30.83. 19F