The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Dec. 03, 1996
Filed:
Oct. 17, 1994
Reuben D Rieke, Lincoln, NE (US);
Board of Regents of the University of Nebraska, Lincoln, NE (US);
Abstract
The magnesium complexes of cyclic hydrocarbons and conjugated dienes, such as 1,2-dimethylenecycloalkanes and 1,3-butadienes, are readily prepared in high yields using highly reactive magnesium. Reactions of these (2-butene-1,4-diyl)magnesium reagents with electrophiles such as dibromoalkanes, alkylditosylates, alkylditriflates, bromoalkylnitriles, esters, or amides serve as a convenient method for synthesizing carbocyclic systems. Significantly, carbocycles prepared by this method contain functional groups such as the exocyclic double bond or a keto group in one of the rings which could be used for further elaboration of these molecules. Furthermore, fused bicyclic systems containing a substituted five-membered ring can be conveniently prepared at high temperatures by the reactions of (2-butene-1,4-diyl)magnesium complexes with carboxylic esters or acid halides whereas low temperatures lead to regioselective synthesis of .beta.,.gamma.-unsaturated ketones. Additionally, .gamma.-lactones, including spiro .gamma.-lactones, can be easily prepared in a one pot synthesis from the reaction of (2-butene-1,4-diyl)magnesium complexes with a ketone or aldehyde and carbon dioxide.