Synthesis of -Nitro--diazocarbonyl Derivatives and Their Applications in the Cyclopropanation of Alkenes and in OH Insertion Reactions
作者:André B. Charette、Ryan P. Wurz、Thierry Ollevier
DOI:10.1002/hlca.200290023
日期:2002.12
a diazo-transfer reaction involving (trifluoromethyl)sulfonyl azide has been developed. These substrates undergo a rhodium-catalyzedcyclopropanation reaction with a variety of alkenes. A systematic study of the reaction indicated that the diastereoselectivity of the cyclopropanation could be effectively controlled through the modification of the steric bulk of the diazo reagent. A novel OH insertion
Synthesis of α-Diazo Carbonyl Compounds with the Shelf-Stable Diazo Transfer Reagent Nonafluorobutanesulfonyl Azide
作者:Jose Luis Chiara、José Ramón Suárez
DOI:10.1002/adsc.201000846
日期:2011.3.7
Nonafluorobutanesulfonyl azide is a shelf‐stable, cost‐effective and general diazo transfer reagent for the efficient synthesis of α‐diazo carbonyl compounds in excellent yields and in very short reaction times, under mild conditions. The diazo products can be readily isolated in pure form after a simple aqueous extractive work‐up that avoids chromatographic purification in most cases. Because of its
Nitrocyclopropanes from nitrodiazomethanes. Preparation and reactivity
作者:P.E. O'Bannon、William P. Dailey
DOI:10.1016/s0040-4020(01)89052-9
日期:——
Nitrodiazo compounds cyclopropanate electron rich alkenes in the presence of rhodium(II) acetate. The yields and diastereoselectivities are dependent on both the alkene and the nitrodiazo precursor. Nitrocyclopropanecarboxylates undergo ring opening, reduction and hydrolysis.
Doubly Activated Cyclopropanes as Synthetic Precursors for the Preparation of 4-Nitro- and 4-Cyano-dihydropyrroles and Pyrroles
作者:Ryan P. Wurz、André B. Charette
DOI:10.1021/ol050442l
日期:2005.6.1
ketones have been prepared in an expedient manner from cyclopropanation reactions of alkenes by diazo compounds or in situ-generated phenyliodonium ylides catalyzed by Rh(II) carboxylates. The doubly activated cyclopropanes were used as synthetic precursors for the regiospecific synthesis of 4-nitro- and 4-cyano-dihydropyrroles upon treatment with primaryamines. Oxidation of the dihydropyrroles with DDQ