- O-Monoacyltartaric acid catalyzed enantioselective conjugate addition of a boronic acid to dienones: application to the synthesis of optically active cyclopentenones.
O-Monoacyltartaric acid catalyzed enantioselective conjugate addition of a boronic acid to dienones: application to the synthesis of optically active cyclopentenones.
Organic letters (2014-09-24)
Masaharu Sugiura, Ryo Kinoshita, Makoto Nakajima
PMID25248134
ABSTRACT
Enantioselective conjugate addition of styrylboronic acid to dienones was effectively catalyzed by an O-monoacyltartaric acid to afford monostyrylated products with good enantioselectivity. The RCM of the monostyrylated products using the Hoveyda-Grubbs II catalyst afforded optically active cyclopentenones, including a synthetic intermediate of the antitumor agent TEI-9826. The study shows that a diene additive such as 1,6-heptadiene or diallyl ether was essential for the RCM.
MATERIALS
Product Number
Brand
Product Description
Sigma-Aldrich
L-(+)-Tartaric acid, puriss., meets analytical specification of Ph. Eur., NF, 99.7-100.5% (calc. to the dried substance), powder
Sigma-Aldrich
L-(+)-Tartaric acid, puriss. p.a., reag. ISO, 99.5-101.0% (calc. to the dried substance)
Supelco
L-(+)-Tartaric acid, certified reference material, TraceCERT®, Manufactured by: Sigma-Aldrich Production GmbH, Switzerland