Remarkable rate acceleration of SmI3-mediated iodination of acetates of Baylis-Hillman adducts in ionic liquid: facile synthesis of (Z)-allyl iodides.
- Author:
Yun-kui LIU
1
;
Hui ZHENG
;
Dan-qian XU
;
Zhen-yuan XU
;
Yong-min ZHANG
Author Information
1. State Key Laboratory Breeding Base of Green Chemistry-Synthesis Technology, Zhejiang University of Technology, Hangzhou 310014, China.
- Publication Type:Journal Article
- MeSH:
Acetates;
chemistry;
Iodides;
chemical synthesis;
Ions;
Kinetics;
Samarium;
chemistry;
Solutions
- From:
Journal of Zhejiang University. Science. B
2006;7(3):193-197
- CountryChina
- Language:English
-
Abstract:
Stereoselective transformation of Baylis-Hillman acetates 1 into corresponding (Z)-allyl iodides 2 has been achieved by treatment of 1 with samarium triiodide in THF. Remarkable rate acceleration of samarium triiodide-mediated iodination of 1 was found when ionic liquid 1-n-butyl-3-methyl-imidazolium tetrafluroborate ([bmim]BF(4)) was used as reaction media in stead of THF. This novel approach proceeds readily at 50 degrees C within a few minutes to afford (Z)-allyl iodides 2 in excellent yields. A mechanism involving stereoselective iodination of the acetates of Baylis-Hillman adducts by samarium triiodide is described, in which a six-membered ring transition state played a key role in the stereoselective formation of 2.