Journal of Organic Chemistry p. 718 - 731 (1993)
Update date:2022-07-29
Topics:
Dittmer, Donald C.
Discordia, Robert P.
Zhang, Yanzhi
Murphy, Christopher K.
Kumar, Archana
et al.
Good yields of enantiomeric allylic alcohols can be obtained in high enantiomeric excess (ee) by combining Sharpless-Katsuki asymmetric epoxidation process (SAE) with tellurium chemistry.The advantages of the tellurium process are as follows: (1) the 50percent yield limitation on the allylic alcohol in the Sharpless kinetic resolution (SKR) can be overcome; (2) allylic tertiary alcohols which are unsatisfactory substrates in the SKR can be obtained in high optical purity; (3) optically active secondary allylic alcohols with tertiary alkyl substituents (e.g. tert-butyl) at C-1 can be obtained in high ee; (4) optically active sterically congested cis secondary alcohols can be obtained in high ee; and (5) the nuisance of the slow SAE of some vinyl carbinols can be avoided.The key step in the reaction sequence is either a stereospecific 1,3-transposition of double bond and alcohol functionalities or an inversion of the alcohol configuration with concomitant deoxygenation of the epoxide function in epoxy alcohols.Trans secondary allylic alcohols can be converted to cis secondary allylic alcohols by way of erythro epoxy alcohols (glycidols); threo glycidyl derivatives are converted to trans secondary allylic alcohols.These transformations are accomplished by the action of telluride ion, generated in situ from the element, on a glycidyl sulfonate ester.Reduction of elemental Te is conveniently done with rongalite (HOCH2SO2Na) in an aqueous medium.This method is satisfactory when Te2- is required to attack at primary carbon site of a glycidyl sulfonate.In cases where Te2- is required to attack a secondary carbon site, reduction of the tellurium must be done with NaBH4 or LiEt3BH.Elemental tellurium is precipitated during the course of the reactions and can be recovered and reused.
View MoreChengdu King-tiger Pharm-chem. Tech. Co., Ltd
Contact:028-85317716
Address:Tianfu Life Science Park, No. 88 South Keyuan Road, Gaoxin District, Chengdu City, Sichuan Province, PRC.
Zhuhai Rundu Pharmaceutical co.,Ltd
Contact:+86-756-7630755
Address:No.6,North Airport Road,Sanzao Town,Jinwan District
JIANGXI ZHANGFENG CHEMICAL CO., LTD.
Contact:+86-0799-3413066
Address:Xiyuan village, Xiabu Town, Xiangdong District
Wuxi Forest Biological Co.,Ltd
Contact:+86-510-81602300
Address:Room 317,Building D, No.159 middle Chengjiang Road,Jiangyin Wuxi city.
Fujian Huitian Biological Pharmacy Co., Ltd.
Contact:0086-598-8300831; 8339920
Address:No.46,Taijiang Road,Sanming City,Fujian,China
Doi:10.1007/BF00471815
(1986)Doi:10.1007/BF00597823
(1987)Doi:10.1016/S0040-4039(00)95314-0
(1987)Doi:10.1016/j.cattod.2017.05.083
(2017)Doi:10.1021/jm00397a026
(1988)Doi:10.1021/jo00238a001
(1988)