5720
A.-C. Dublanchet et al. / Tetrahedron 58 (2002) 5715±5721
Resin 14-b. Resin 10-b (5.0 g, 1.2 mmol), pyridine (0.32 ml,
3.96 mmol), 10-undecenoyl chloride (0.8 ml, 3.72 mmol),
(CS); 178.83 (COOH); 168.26 (NCO); 134.30 (CH);
131.85 (C); 123.61 (CH); 70.48 (CH2); 48.77 (CH); 41.00
(CH2); 31.23 (CH2); 26.93 (CH2); 13.72 (CH3). MS(IC1):
368 (M1H)1, 385 (M1NH4)1.
CH2Cl2 (10 ml) gave 5.05 g (84% yield, l0.2 mmol g21
)
1
of resin 14-b. H NMR: 5.80 (m, 1H); 5.02 (s, 2H); 5.05±
4.95 (dd, 2H); 4.20±4.00 (m, 2H); 4.00±3.80 (m, 2H). IR:
3025, 2926, 1734, 1601, 1493, 1542, 1246, 908, 760, 700.
Table 1, entry 4. Xanthate 11-c (3 g, 15.46 mmol), ole®n 12
(3.82 g, 20.42 mmol, 1.3 equiv.), 1,2-DCE (15 ml), DLP
(330 mg, 5 mol%). Silica gel chromatography(petroleum
ether/ether 4:1 to 1:1) furnished 4.91 g (83% yield) of
5.2. Radical additions. General procedure and work up
for radical additions
1
adduct 13-b. H NMR: 7.86 (m, 2H); 7.74 (m, 2H); 4.61
(m, 2H); 4.18 (m, 1H); 4.04±3.91 (m, 2H); 3.67 (s, 3H);
2.63±2.47 (m, 2H); 2.15 (m, 1H); 1.93 (m, 1H); 1.42 (t, J
7.1 Hz, 3H). 13C NMR: 212.24 (CS); 173.01 (COOMe);
168.11 (NCO); 134.22 (CH); 131.85 (C); 123.51 (CH);
70.37 (CH2); 51.83 (CH3); 48.84 (CH); 40.98 (CH2);
31.20 (CH2); 26.82 (CH2); 13.70 (CH3). IR: 2951, 1773,
1714, 1434, 1393, 1361, 1219, 1112, 1046, 714. MS(IC1):
382 (M1H)1, 399 (M1NH4)1. Anal. calcd for
C17H19NO5S2: C 53.53%; H 5.02%. Found: C 53.52%;
H 4.97%.
A mixture of the xanthate and the ole®n in 1,2-dichloro-
ethane (1,2-DCE) was degassed under argon for 30 min at
re¯ux then catalytic amounts (5±10 mol%) of DLP were
added every2 h. The reactions with Wang resin were
monitored byTLC and/or 1H NMR on cleaved aliquots of
the reaction medium. The reactions with the soluble ana-
1
logue of Wang resin were monitored by H NMR (ns128
or 256 scans, D10.5 s) of aliquots of the reaction medium.
1
The conversions were determined by H NMR analysis of
crude products after TFA cleavage. For the reference reac-
tions in solution, the resulting adducts were puri®ed after
evaporation of the solvent bysilica gel chromatography. For
reactions with Wang polymer, the resin was ®ltered and
washed several times with CH2Cl2, CH2Cl2/pentane (1:1),
THF and ether then dried several hours under vacuum at
508C before cleavage and silica gel chromatography. For
reactions with soluble analogue of Wang resin, the
1,2-dichloroethane (1,2-DCE) was evaporated in vacuo
before precipitation, drying, cleavage and silica gel chroma-
tography. The carboxylic adducts (13-a and 16) obtained
from supported radical additions were compared with the
corresponding methyl ester derivative 13-b for compound
13-a, and with authentic sample obtained from reference
reactions in solution for adduct 16.
5.2.2. Radical additions to immobilized ole®ns 14-a and
14-b (Scheme 6, Table 2). Table 2, entry 1. Resin 14-a
(400 mg, 0.42 mmol), xanthate 15 (500 mg, 2.08 mmol,
5.0 equiv.), 1,2-DCE (2 ml), DLP (89 mg, 54 mol%). The
1H NMR analysis of the crude product after cleavage
showed a conversion of 80% and the presence of adduct
16 and tetralone 17 in a 9:1 ratio. Silica gel chromatography
(petroleum ether/ether 7:3, 1% AcOH) furnished 72 mg of
products 16 and 17 in 9:1 ratio (42% yield, 52% corrected
for conversion).
Table 2, entry 2. Resin 14-b (900 mg, 0.18 mmol), xanthate
15 (156 mg, 0.65 mmol, 3.6 equiv.), 1,2-DCE (0.5 ml), DLP
(45 mg, 50 mol%). The H NMR analysis of the crude
1
product after cleavage showed a conversion of 75% and
the presence of adduct 16 and tetralone 17 in a 9:1 ratio.
Silica gel chromatography(petroleum ether/ether 7:3, 1%
AcOH) furnished 39 mg of products 16 and 17 in 9:1 ratio
(52% yield, 70% corrected for conversion).
5.2.1. Radical additions to N-allylphtalimide 12 (Scheme
4, Table 1). Table 1, entry 1. Resin 11-a (200 mg,
0.21 mmol), ole®n 12 (51 mg, 0.27 mmol, 1.3 equiv.),
1,2-DCE (1 ml), DLP (92 mg, 108 mol%). 1H NMR
analysis of the crude product after cleavage (32 mg) showed
a conversion of 60% and the presence of different
by-products.
Table 2, entry 3. 10-Undenenoic acid 14-c (185 mg,
1.0 mmol), xanthate 15 (734 mg, 3.05 mmol), 1,2-DCE
(1 ml), DLP (47 mg, 12 mol%). Silica gel chromatography
(petroleum ether/ether 7:3, 1% AcOH) furnished 338 mg
Table 1, entry 2. Resin 11-a (400 mg, 0.43 mmol), ole®n 12
(800 mg, 4.28 mmol, 10 equiv.), 1,2-DCE (2 ml). Addition
of DLP (55 mg, 32 mol%) until complete disappearance
1
(80% yield) of adduct 16. H NMR: 7.95 (m, 2H); 7.57
1
(m, 1H); 7.47 (m, 2H); 4.61 (m, 2H); 3.83 (m, 1H); 3.15
(m, 2H); 2.35 (t, J7.5 Hz, 2H); 2.26 (m, 1H); 1.99(m, 1H);
1.72 (m, 2H); 1.64 (m, 2H); 1.46 (m, 2H); 1.39 (t, J7.1 Hz,
3H) 1.37±1.28 (m, 8H). 13C NMR: 214.61 (CS); 199.61
(CO); 180.10 (COOH); 136.86 (C); 133.21 (CH); 128.69
(CH); 128.16 (CH); 69.96 (CH2); 51.19 (CH); 35.91
(CH2); 34.82 (CH2); 34.13 (CH2); 29.42 (CH2); 29.30
(CH2); 29.21 (CH2); 29.07 (CH2); 28.70 (CH2); 26.90
(CH2); 24.72 (CH2); 13.84 (CH3). IR: 3700±2800, 2927,
2854, 1707, 1686, 1448, 1212, 1111, 1050. MS(IC1): 426
(M1H)1, 443 (M1NH4)1, 303. Anal. calcd for C22H32O4S2:
C 62.23%; H 7.60%. Found: C 62.12%; H 7.64%.
of the starting xanthate observed by H NMR. Silica gel
chromatography(ether, 1±2% MeOH) followed byprepara-
tive TLC (ether, 2% MeOH) furnished 51 mg (32% yield)
of adduct 13-a of approximately80% puritychecked by
LC-MS (26% corrected yield).
Table 1, entry 3. Resin 11-b (1.0 g, 0.20 mmol); ole®n 12
(132 mg, 0.66 mmol, 3.3 equiv.), 1,2-DCE (1 ml). Addition
of DLP (40 mg, 40 mol%) until complete disappearance of
1
the starting xanthate observed by H NMR. Cleavage and
silica gel chromatography(ether/petroleum ether 1:1, 1%
AcOH) furnished 50 mg (68% yield) of adduct 13-a of
approximately80% puritychecked by 1H NMR with TPM
as internal reference (54% corrected yield). Adduct 13-a. 1H
NMR: 7.87 (m, 2H); 7.74 (m, 2H); 4.60 (m, 2H); 4.18 (m,
1H); 4.05±3.90 (m, 2H); 2.70±2.49 (m, 2H); 2.13 (m, 1H);
1.92 (m, 1H); 1.42 (t, J7.1 Hz, 3H). 13C NMR: 212.15
Acknowledgements
We thank Professor GuyLippens for helpful discussion on