Rapid and Efficient Protocol for the Synthesis of 4-Chlorotetrahydropyrans Using Niobium(V) Chloride
作者:J. S. Yadav、B. V. Reddy、Manoj Kumar Gupta、Swapan Kumar Biswas
DOI:10.1055/s-2004-831220
日期:——
Aldehydes undergo a rapid coupling with 3-buten-1-ol utilizing 20 mol% of niobium(V) chloride to afford 4-chlorotetrahydropyran derivatives under extremely mild conditions within short reaction times in excellent yields with high selectivity. The similar halogenated tetrahydropyrans are also obtained using gallium(III) halides.
CeCl<sub>3</sub>·7H<sub>2</sub>O/LiI: A Novel Reagent System for the Synthesis of 4-Iodotetrahydropyrans via Prins Cyclization
作者:J. S. Yadav、B. V. Subba Reddy、G. G. K. S. Narayana Kumar、G. Madhusudhan Reddy
DOI:10.1246/cl.2007.426
日期:2007.3.5
Homoallylic alcohols undergo smooth coupling with a variety of aldehydes in the presence of CeCl3·7H2O–LiI reagent system in refluxing dichloroethane under neutral conditions to produce the corresponding 4-iodotetrahydropyran derivatives in high yields. The spirocyclic-4-iodotetrahydropyrans are obtained in case of cyclic ketones.