Selenium-induced cyclization of O-allyl oximes as a synthetic route to N-alkyl isoxazolidines
摘要:
Phenylseleneyl bromide easily reacts with O-allyl oximes to afford cyclic iminium bromides which can be reduced in situ with sodium borohydride to produce substituted N-alkyl isoxazolidines in good yield.
The organoselenium-induced ring-closure reactions of O-allyl oximes give cyclic iminium salts which react with water to afford isoxazolidines in good yield.
O-烯丙基肟的有机硒诱导的闭环反应生成环状亚胺盐,其与水反应以高收率得到异恶唑烷。
Optically active isoxazolidines and 1,3-amino alcohols by asymmetric selenocyclization reactions of O-allyl oximes
The selenyl triflate generated from the reaction of di-2-[(1S)-1-(methylthio)ethyl]phenyl diselenide with silver triflate reacts with various substituted O-allyl oximes to promote ring closure, which affords optically active isoxazolidines in high yields and with good diastereoselectivity (up to 93:7). Enantiomerically enriched 1,3-aminoalcohols can be easily obtained by NO bond cleavage of these
Disclosed are compounds of Formula 1, including all stereoisomers, N-oxides, and salts thereof,
wherein
E, X, G, W
2
and Z are as defined in the disclosure.
Also disclosed are compositions containing the compounds of Formula 1 and methods for controlling plant disease caused by a fungal pathogen comprising applying an effective amount of a compound or a composition of the invention.
Also disclosed are compounds of Formula 1A including all stereoisomers, N-oxides, and salts thereof,
wherein
E, X, G and Z
1
are as defined in the disclosure.
Also disclosed is the use of the compounds of Formula 1A as intermediates for preparing compounds of Formula 1.
Phenylseleneyl bromide easily reacts with O-allyl oximes to afford cyclic iminium bromides which can be reduced in situ with sodium borohydride to produce substituted N-alkyl isoxazolidines in good yield.