1,5-Asymmetric induction in boron-mediated aldol reactions of beta-alkoxy methylketones.
Good levels of substrate-controlled, 1,5- syn-stereoinduction are obtained in boron-mediated aldol reactions of beta-trichloromethyl-beta-alkoxy and beta-trifluoromethyl-beta-alkoxy methylketones with achiral aldehydes, independent of the nature of the beta-alkoxy protecting group (TBS or PMB). In the case of boron aldol reactions of beta-aryl-beta-alkoxy methylketones, the 1,5- anti-adducts were obtained with high levels of diastereoselectivity only with a beta-OPMB group.
Dias
Luiz C
LC
Instituto de Química, Universidade Estadual de Campinas, UNICAMP, C.P. 6154, 13084-971 Campinas, SP, Brazil. ldias@iqm.unicamp.br
de Marchi
Anderson A
AA
Ferreira
Marco A B
MA
Aguilar
Andrea M
AM
D000438:Alcohols / Q000737:chemistry*; D000447:Aldehydes / Q000737:chemistry*; D001896:Boron Compounds / Q000737:chemistry*; D007659:Ketones / Q000138:chemical synthesis / Q000737:chemistry*; D013237:Stereoisomerism
D000438:Alcohols; D000447:Aldehydes; D001896:Boron Compounds; D007659:Ketones