N-hydroxypyridine-2(1H)-thione derivatives of carboxylic acids as activated esters. Part I. The synthesis of carboxamides
作者:Derek H.R. Barton、J. Albert Ferreira
DOI:10.1016/0040-4020(96)00487-5
日期:1996.7
The reaction between an acyl derivative of N-hydroxypyridine-2(1H)-thione (a Barton PTOC ester) and either an amine (primary or secondary), or the corresponding sulfenamide, led to the formation of a carboxamide in a clean transformation requiring minimal work-up and purification. The reaction with a sulfenamide is particularly useful since the only by-product, an unsymmetrical disulfide, is of both
Unified Synthesis of Quinone Sesquiterpenes Based on a Radical Decarboxylation and Quinone Addition Reaction
作者:Taotao Ling、Erwan Poupon、Erik J. Rueden、Sun H. Kim、Emmanuel A. Theodorakis
DOI:10.1021/ja027517q
日期:2002.10.1
several quinone sesquiterpenes is described herein. Essential to this strategy is a novel radical additionreaction that permits the attachment of a fully substituted bicyclic core 16 to a variably substitutedquinone 10. The addition product 15 can be further functionalized, giving access to natural products with a high degree of oxygenation at the quinone unit. The quinoneadditionreaction is characterized
The reaction of various olefins with carbon radicals generated by photolysis of Barton-esters finishes adducts suitable for transformation into the corresponding malonic acids.
The role of organic tellurides as accumulators and exchangers of carbon radicals
作者:Derek H.R. Barton、Nubar Ozbalik、Jadab C. Sarma
DOI:10.1016/s0040-4039(00)82402-8
日期:1988.1
Primary carbon radicals, generated by photolysis of acyl derivatives of -hydroxy-2-thiopyridone, exchange efficiently on diisopropyl telluride to give isopropylradicals which can in turn be trapped by radicophilic olefins.
A new synthesis of thiols in high yield utilizing carbon radicals and elemental sulfur is demonstrated. The procedure is applicable to 1°, 2° and 3° carboxylic acids.