4878
F. F. Kneisel et al. / Tetrahedron Letters 43 (2002) 4875–4879
Cl
OAc
26
R
I
OAc
26, i
iii
N
Ts
H
H
R
I
R
cis-23: 76%
NH
Ts
N
Ts
25a: R=H
25b: R=CO2Et
27: R=H; 95%
R
I
OAc
28: R=CO2Et; 69%
iv
26, ii
N
Ts
trans-23: R=H; 89%
trans-24: R=CO2Et; 35%
Scheme 4. Reagents and conditions: (i) Pd(PPh3)4 (10 mol%), rt, 16 h; (ii) K2CO3, DMSO, 80°C, 22 h; (iii) i-PrMgCl, CuCN·2LiCl
or Co(acac)2 cat.; (iv) i-PrMgCl, −10°C to rt, anti-substitution.
References
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