Iron-mediated intramolecular metalative cyclization of alpha,beta-unsaturated esters and amides. Versatile one-pot preparation of bicyclic ketoesters.
2-Nonen-7-ynedioic or 2-decen-8-ynedioic acid derivatives were treated with an iron reagent generated from FeCl2 and t-BuMgCl in a ratio of 1:4 to give cyclized products after hydrolysis, deuteriolysis, or the addition of carbonyl compounds. Upon reaction with the same iron reagent, 2,7-nonadienedioates afforded bicyclic ketoesters (and their enol forms) after the addition of s-BuOH or carbonyl compounds.
Department of Biomolecular Engineering, Graduate School of Bioscience and Biotechnology, Tokyo Institute of Technology, 4259-B-59 Nagatsuta-cho, Midori-ku, Yokohama, Kanagawa 226-8501, Japan.
Takeshi
T
Hata
Naoki
N
Hirone
Shiro
S
Sujaku
Kirihiro
K
Nakano
Hirokazu
H
Urabe
D000577:Amides / Q000737:chemistry*; D019086:Bridged Bicyclo Compounds, Heterocyclic / Q000138:chemical synthesis* / Q000737:chemistry; D003500:Cyclization; D004952:Esters / Q000138:chemical synthesis* / Q000737:chemistry; D007501:Iron / Q000737:chemistry*; D007659:Ketones / Q000737:chemistry*; D015394:Molecular Structure
D000577:Amides; D019086:Bridged Bicyclo Compounds, Heterocyclic; D004952:Esters; D007659:Ketones; D007501:Iron