M. Sakamoto et al. / Tetrahedron 56 (2000) 6795±6804
6803
General procedure for the photochemical reaction in
benzene
tallographic analysis: monoclinic space group P212121,
Ê
Ê
Ê
a8.8350 (9) A, b30.294 (5) A, c6.295 (2) A, V
Ê 3
1684.9 (6) A , Z4, r1.165 g/cm3, m(CuKa)
A benzene solution of thioamide 1a±1d (0.02 M) was
purged with deoxygenated and dried argon for 15 min
prior to photolysis and was irradiated with a 500 W Eikosha
high-pressure mercury lamp through a Pyrex ®lter. After
irradiation, benzene was evaporated and the photolysate
was chromatographed on silica gel (Merk Kieseigel 60)
with ethyl acetate±hexane (10:1) as the eluent.
16.29 cm21. The structure was solved by the direct method
and re®ned by the method of full-matrix least-squares. The
absolute con®guration was solved by the Bijvoet difference
method. For 2223 Friedel pairs, 438 agreement and 241
disagreement between observed and calculated DF for the
structure with the (3S,4S)-con®guration clearly showed that
this structure is that with the correct absolute con®guration,
where the ®nal R and Rw were 0.055 and 0.064 for 3678
re¯ections.
General procedure for the photochemical reaction in the
solid-state
(R)-1-Benzyl-4-phenylazetidine-2-thione-3-spiro-10-cyclo-
hexane 2c was obtained as colorless prismatic crystals from
hexane±chloroform: mp 109±1108C; [a]2D011168 (c1.0
in CHCl3); IR (cm21, KBr) 1495; UV (nm, C6H12) 269 (e
16200); 1H NMR (CDCl3) d 0.5±0.7 (m, 1H, CH2), 1.2±1.7
(m, 7H, CH2), 1.8±2.0 (m, 2H, CH2), 3.99 and 5.43 (ABq,
2H, J14.5 Hz, CH2Ph), 4.63 (s, 1H, 4-CH), 7.1±7.4 (m,
10H, ArH); 13C NMR (CDCl3) d 21.4 (t, CH2), 23.1 (t, CH2),
24.8 (t, CH2), 27.8 (t, CH2), 34.3 (t, CH2), 44.1 (t, CH2Ph),
61.5 (s, 3-C), 73.8 (d, 4-C), 127.5 (d, Ar), 128.0 (d, Ar),
128.5 (d, Ar), 128.6 (d, Ar), 128.7 (d, Ar), 128.8 (d, Ar),
134.2 (s, Ar), 134.6 (s, Ar), 210.8 (s, CvS); LRMS (FAB)
Calcd for C20H30NS2: m/z 322. Anal. Calcd for C21H23NS:
C, 78.46%; H, 7.21%; N, 4.36%. Found: C, 78.66%; H,
7.39%; N, 4.34%.
All of the solid-state photolyses were done under an atmos-
phere of deoxygenated and dried argon. Solid samples
placed in the test tube were cooled in a cooling apparatus,
and were irradiated with a 500 W high-pressure mercury
lamp. After irradiation, the photolysate was treated the
same as that in solution photochemistry.
(E)-N,N-Dibenzyltiglylthioamide (E)-1a was analyzed for
1H and 13C NMR spectroscopy as a crude reaction mixture:
1H NMR (CDCl3) d 1.68 (d, J6.8 Hz, 3H, MeCHvC),
1.99 (s, 3H, CHvCMe), 4.71 (s, 2H, CH2Ph), 5.25 (s, 2H,
CH2Ph), 5.58 (dq, J1.5 and 7.0 Hz, 1H, MeCHvC), 7.1±
7.4 (m, 5H, ArH); 13C NMR (CDCl3) d 13.4 (q, MeCHvC),
16.5 (q, CHvCMe), 52.3 (t, CH2Ph), 54.6 (t, CH2Ph), 122.1
(d, MeCHvC), 127.2 (d, Ar), 127.4 (d, Ar), 127.9 (d, Ar),
128.0 (d, Ar), 128.6 (d, Ar), 128.7 (d, Ar), 135.0 (s, Ar),
135.3 (s, Ar), 138.7 (s, MeCHvC), 207.1 (s, CvS).
The absolute con®guration was determined by X-ray crys-
tallographic analysis: monoclinic space group P43,
3
Ê
Ê
Ê
a10.366 (1) A, c17.133 (3) A, V1841.0 (4) A , Z4,
r1.160 g/cm3, m(CuKa)15.30 cm21. The structure was
solved by the direct method and re®ned by the method of
full-matrix least-squares. The absolute con®guration was
solved by the Bijvoet difference method. For 2391 Friedel
pairs, 675 agreement and 351 disagreement between
observed and calculated DF for the structure with the (R)-
con®guration clearly showed that this structure is that with
the correct absolute con®guration, where the ®nal R and Rw
were 0.052 and 0.071 for 3226 re¯ections.
(Z)-1-Benzyl-3-ethyl-3-methyl-4-phenylazetidine-2-thione
2a was obtained as colorless prismatic crystals from
hexane±chloroform: mp 61±628C; IR (cm21, KBr) 1496;
1
UV (nm, in C6H12) 268 (e 15800); H NMR (CDCl3) d
0.56 (t, J7.3 Hz, 3H, CH2CH3), 1.25 (m, 1H, CH2CH3),
1.34 (s, 3H, C(Et)Me), 1.53 (m, 1H, CH2CH3), 4.03 and 5.44
(ABq, J14.3 Hz, 2H, CH2Ph), 4.60 (s, 1H, CHPh), 7.1±7.4
(m, 10H, ArH); 13C NMR (CDCl3) d 7.7 (q, CH2CH3), 16.8
(q, C(Et)Me), 25.3 (t, CH2CH3), 46.2 (t, CH2Ph), 60.2 (s,
C(Et)Me), 73.8 (s, CHPh), 128.4 (d, Ar), 128.6 (d, Ar),
128.7 (d, Ar), 128.8 (d, Ar), 128.9 (d, Ar), 134.3 (s, Ar),
134.5 (s, Ar), 211.3 (s, CvS); LRMS (FAB) Calcd for
C20H30NS2: m/z 296.
1-Benzyl-4-phenylazetidine-2-thione-3-spiro-10-cyclohep-
tane 2d was obtained as colorless prismatic crystals from
hexane±chloroform: mp 92±92.58C; IR (cm21, KBr) 1495;
UV (nm, in C6H12) 239 (e 10300), 268 (e 16000); 1H NMR
(CDCl3) d 0.9±1.1 (m, 1H, CH2), 1.2±1.9 (m, 8H, CH2),
2.0±2.1 (m, 1H, CH2), 3.99 and 5.43 (ABq, 2H, J14.5 Hz,
CH2Ph), 4.64 (s, 1H, 4-CH), 7.1±7.4 (m, 10H, ArH); 13C
NMR (CDCl3) d 23.2 (t, CH2), 24.1 (t, CH2), 29.7 (t, CH2),
29.8 (t, CH2), 31.8 (t, CH2), 37.0 (t, CH2), 46.7 (t, CH2Ph),
64.3 (s, 3-C), 75.0 (d, 4-C), 127.8 (d, Ar), 128.4 (d, Ar),
128.8 (d, Ar), 129.1 (d, Ar), 129.2 (d, Ar), 134.9 (s, Ar),
135.0 (s, Ar), 212.7 (s, CvS); Anal. Calcd for C21H23NS: C,
78.76%; H, 7.51%; N, 4.17%. Found: C, 78.63 %; H, 7.56
%; N, 4.02 %.
(3S,4S)-1-Benzyl-3-isopropyl-4-phenylazetidine-2-thione
2b was obtained as colorless prismatic crystals: mp 94±
958C; [a]2D01738, c1.0 in CHCl3); IR (cm21, KBr)
1
1496; UV (nm, C6H12) 243 (e 9600), 274 (e 15600); H
NMR (CDCl3) d 0.35 (d, 3H, J6.6 Hz, CHMe2), 1.30 (d,
3H, J6.6 Hz, CHMe2), 1.80 (m, 1H, CHMe2), 3.02 (dd,
1H, J4.7 and 11.5 Hz, CHPri), 3.96 and 5.37 (ABq, 2H,
J14.4 Hz, CH2Ph), 4.99 (d, 1H, J4.6 Hz, CHPh), 7.1±
7.4 (m, 10H, ArH); 13C NMR (CDCl3) d 20.3 (q, CHMe2),
26.7 (d, CHMe2), 46.4 (d, CHPri), 65.7 (t, CH2Ph), 67.9 (s,
CHPh), 127.9 (d, Ar), 128.0 (d, Ar), 128.2 (d, Ar), 128.6 (d,
Ar), 128.7 (d, Ar), 128.8 (d, Ar), 128.9 (d, Ar), 134.0 (s, Ar),
134.3 (s, Ar), 204.9 (s, CvS). Anal. Calcd for C19H21NS: C,
77.24%; H, 7.16%; N, 4.74%. Found: C, 77.26%; H, 7.24%;
N, 4.77%.
References
1. (a) Scheffer, J. R.; Garcia-Garibay, M.; Nalamasu, O. Organic
Photochemistry; Padwa, A., Ed.; Marcel Dekker: New York and
Basel, 1987; Vol. 8, pp 249. (b) Gamlin, J. N.; Jones, R.; Leibovitch,
The absolute con®guration was determined by X-ray crys-