Photoinduced Deoxygenative Borylations of Aliphatic Alcohols
作者:Jingjing Wu、Robin M. Bär、Lin Guo、Adam Noble、Varinder K. Aggarwal
DOI:10.1002/anie.201910051
日期:2019.12.19
A photochemical method for converting aliphatic alcohols into boronic esters is described. Preactivation of the alcohol as a 2-iodophenyl-thionocarbonate enables a novel Barton-McCombie-type radical deoxygenation that proceeds efficiently with visible light irradiation and without the requirement for a photocatalyst, a radical initiator, or tin or silicon hydrides. The resultant alkyl radical is intercepted
This paper describes an efficient procedure for selective 3'-O- or 3-N-protection of 5'-O-tert-butyldimethylsilylthymidine, depending on the use of aprotic polar solvents with low or high dielectric constant, respectively. These syntheses were activated by either ultrasound or microwaves. Several alkyl bromides offer a convenient route to prepare 3'-O- or 3-N-protected and functionalized thymidine derivatives. (C) 2008 Elsevier Ltd. All rights reserved.