Preparation of a cycloheptane ring from a 1,2-diketone with high stereoselectivity
Yoshiaki Takada1, Kenichi Nomura, Seijiro Matsubara
1Department of Material Chemistry, Graduate School of Engineering, Kyoto University, Kyoudai-Katsura, Nishikyo, Kyoto 615-8510, Japan.
Abstract:
Treatment of 1,6-dialkylhexa-1,5-diene-3,4-diones with bis(iodozincio)methane gave zinc alkoxides of cis-5,6-dialkylcyclohepta-3,7-diene-1,3-diol in good yields at room temperature. The reaction proceeded with high stereospecificity. Bis(iodozincio)methane converted the diketone into the cis-divinylcyclopropane-1,2-diol stereoselectively; this diol transformed into the corresponding cycloheptane derivative stereospecifically via Cope rearrangement.
More Related Videos
09:45Accessing Valuable Ligand Supports for Transition Metals: A Modified, Intermediate Scale Preparation of 1,2,3,4,5-Pentamethylcyclopentadiene
Published on: March 20, 2017
09:35Preparation of a Corannulene-functionalized Hexahelicene by Copper(I)-catalyzed Alkyne-azide Cycloaddition of Nonplanar Polyaromatic Units
Published on: September 18, 2016
Related Concept Videos
Diels–Alder Reaction Forming Cyclic Products: Stereochemistry
Diels–Alder Reaction Forming Bridged Bicyclic Products: Stereochemistry
Cyclohexenones via Michael Addition and Aldol Condensation: The Robinson Annulation
[4+2] Cycloaddition of Conjugated Dienes: Diels–Alder Reaction
Intramolecular Claisen Condensation of Dicarboxylic Esters: Dieckmann Cyclization
Preparation of Epoxides
Epoxides result from alkene oxidation, which can be achieved by a) air, b) peroxy acids, c) hypochlorous acids, and d) halohydrin cyclization.
Epoxidation with Peroxy Acids
Epoxidation of alkenes via oxidation with peroxy acids involves the conversion of a carbon–carbon double bond to an epoxide using the oxidizing agent meta-chloroperoxybenzoic acid, commonly known as MCPBA. Since the O–O bond of peroxy acids is very weak, the addition of electrophilic oxygen of peroxy acids to...
