. Author manuscript; available in PMC: 2008 Dec 8.

Published in final edited form as: Org Lett. 2007 Oct 12;9(23):4849–4852. doi: 10.1021/ol702185y

Table 1.

Selected conditions for the syn addition of 2-furylzinc halides to 4α-epoxypyranoside 7 in the presence of ZnX₂^a


entry	furylZnX, equiv	ZnX₂ (equiv)	yield ^b
1	2	ZnCl₂ (2)	41%
2	2	ZnCl₂ (5)	60%
3	4	ZnCl₂ (2)	64%
4	10	ZnCl₂ (2)	76%
5	2	ZnBr₂ (0)	56%
6	2	ZnBr₂ (2)	67%
7	2	ZnBr₂ (5)	83%

Preparation of 2-furylzinc halide in THF: (i) Furan, n-BuLi, THF, −78 ºC, 30 min; (ii) ZnX₂, THF, 0 ºC, 30 min. Epoxide 7 was added as a CH₂Cl₂ solution at −78 ºC, warmed to 0 ºC, then stirred for 2 h while warming to rt.

Isolated yields.