Abstract

T. Vijaya Durga¹, K. Bala Murali Krishna¹, M. Baby ramana¹, M. Shantha Kumari², K. Vijay³ and B. Hari Babu¹

DOI : http://dx.doi.org/10.13005/ojc/330260

Bismuth trichloride as mild reagent, has been found to be a worthful catalyst for  tetrahydropyranylation of 1º, 2 º, 3º, allylic, benzylic alcohols, and symmetric di-ols. At room temperature the reagent THP(3,4–dihydro-2H-pyran) was successfully employed as pyranylating agent in presence of BiCl₃ catalyst without the use of a solvent and the yields of the products were found to be 90-96%. Further, the depyranylation of alcohols was achieved in quantitative yield by simple addition of MeOH using the same catalyst. The developed method was showed good chemo-selectivity in symmetrical diols  for mono THP protection.

Bismuth trichloride; tetrahydropyranylation; depyranylation; alcohols; symmetrical diols

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