Diastereoselectivity Control in Formal Nucleophilic Substitution of Bromocyclopropanes with Oxygen- and Sulfur-Based Nucleophiles
作者:Joseph E. Banning、Anthony R. Prosser、Bassam K. Alnasleh、Jason Smarker、Marina Rubina、Michael Rubin
DOI:10.1021/jo200368a
日期:2011.5.20
diastereoconvergent formal nucleophilicsubstitution of bromocyclopropanes with oxygen- and sulfur-based nucleophiles is described. The reaction proceeds via in situ formation of a highly reactive cyclopropene intermediate and subsequent diastereoselective addition of a nucleophile across the strained C═C bond. Three alternative means of controlling the diastereoselectivity of addition have been demonstrated:
Templated assembly of medium cyclic ethers via exo-trig nucleophilic cyclization of cyclopropenes
作者:Bassam K. Alnasleh、Marina Rubina、Michael Rubin
DOI:10.1039/c6cc02178f
日期:——
A novel method for the assembly of medium heterocycles via an intramolecular nucleophilic addition to cyclopropenes generated in situ from the corresponding bromocyclopropanes is described. The exo-trig nucleophilic cyclizations were...
Synthesis of Cyclopropenes via
1,2-Elimination of Bromocyclopropanes Catalyzed by Crown
Ether
作者:Michael Rubin、William Sherrill、Ryan Kim
DOI:10.1055/s-0028-1088122
日期:——
synthetic protocol for the preparation of 3,3-disubstituted cyclopropenes from the corresponding bromocyclopropanes via a base-assisted 1,2-elimination has been developed. Employment of catalytic amounts of 18-crown-6 in ethereal solvents allowed for improved yields, as compared to the classical procedure employing dimethyl sulfoxide, making this protocol applicable to the synthesis of hydrophilic cyclopropenes
Intramolecular nucleophilic addition of carbanions generated from <i>N</i>-benzylamides to cyclopropenes
作者:Vladimir Maslivetc、Colby Barrett、Nicolai A. Aksenov、Marina Rubina、Michael Rubin
DOI:10.1039/c7ob02068f
日期:——
An unusual reaction is described, involving a formal intramolecular nucleophilic substitution of bromocyclopropanes with nitrogen ylides generated in situ from N-benzyl carboxamides. It is shown that this reaction involves cyclopropene intermediates and allows for the facile and expeditious preparation of 3-azabicyclo[3.1.0]hexan-2-one scaffolds.