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[1+1+1] Cyclotrimerization for the Synthesis of Cyclopropanes.

ABSTRACT: The synthesis of small rings by functionalization of C(sp(3) )-H bonds remains a great challenge. We report for the first time a copper-catalyzed [1+1+1] cyclotrimerization of acetophenone derivatives under mild reaction conditions. The reaction has a broad scope for the stereoselective synthesis of cyclopropanes by trimerization of acetophenone. The developed transformation is based on an extraordinary copper-catalyzed cascade process that allows saturated carbocycles to be obtained for the first time by cyclotrimerization through functionalization of C(sp(3) )-H bonds. The cascade of sixfold C(sp(3) )-H bond functionalization allows the synthesis of cyclopropanes in a highly stereoselective approach.

SUBMITTER: Manna S

PROVIDER: S-EPMC5071660 | biostudies-literature | 2016 Apr

REPOSITORIES: biostudies-literature

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[1+1+1] Cyclotrimerization for the Synthesis of Cyclopropanes.

Manna Srimanta S Antonchick Andrey P AP

Angewandte Chemie (International ed. in English) 20160321 17

The synthesis of small rings by functionalization of C(sp(3) )-H bonds remains a great challenge. We report for the first time a copper-catalyzed [1+1+1] cyclotrimerization of acetophenone derivatives under mild reaction conditions. The reaction has a broad scope for the stereoselective synthesis of cyclopropanes by trimerization of acetophenone. The developed transformation is based on an extraordinary copper-catalyzed cascade process that allows saturated carbocycles to be obtained for the fir ...[more]

PMID: 26997466

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