Format

Send to

Choose Destination
See comment in PubMed Commons below
Angew Chem Int Ed Engl. 2014 Mar 17;53(12):3187-91. doi: 10.1002/anie.201306186. Epub 2014 Feb 19.

A new type of donor-acceptor cyclopropane reactivity: the generation of formal 1,2- and 1,4-dipoles.

Author information

1
N.D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, 47 Leninsky prosp., 119991 Moscow (Russian Federation); V. A. Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, 32 Vavilov st., 119991 Moscow (Russian Federation).

Abstract

A new type of donor-acceptor cyclopropane reactivity has been discovered. On treatment with anhydrous GaCl3 , they react as sources of even-numbered 1,2- and 1,4-dipoles instead of the classical odd-numbered 1,3-dipoles due to migration of positive charge from the benzyl center. This type of reactivity has been demonstrated for new reactions, namely, cyclodimerizations of donor-acceptor cyclopropanes that occur as [2+2]-, [3+2]-, [4+2]-, [5+2], [4+3]-, and [5+4]-annulations. The [4+2]-annulation of 2-arylcyclopropane-1,1-dicarboxylates to give polysubstituted 2-aryltetralins has been developed in a preparative version that provides exceedingly high regio- and diastereoselectivity and high yields. The strategy for selective hetero-combination of donor-acceptor cyclopropanes was also been developed. The mechanisms of the discovered reactions involving the formation of a comparatively stable 1,2-ylide intermediate have been studied.

KEYWORDS:

annulation; carbocycles; cyclodimerization; donor-acceptor systems; lewis acids

PMID:
24554497
DOI:
10.1002/anie.201306186
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for Wiley
    Loading ...
    Support Center