Stereospecific alkylation of substituted adenines by the mitsunobu coupling reaction under microwave-assisted conditions García Rubiño, María Eugenia Núñez Carretero, María Del Carmen Choquesillo Lazarte, Duane García Ruiz, Juan Manuel Madrid, Yolanda Campos Rosa, Joaquín María Alkylated aminopurines Mitsunobu reaction X-ray crystallography A novel and efficient synthetic method has been developed for the preparation of alkylated aminopurines (N,N-dimethyl-, 2-chloro-N-methyl-, and N-methyladenines) with achiral and chiral 3,4-dihydro-2H-1,5-benzoxathiepin-3-ol by the Mitsunobu reaction under microwave-assisted conditions. This reaction reveals a complete inversion of the stereogenic centre of the secondary alcohol giving an alkylated purine linked to a homochiral six-membered ring. Fifty novel purine derivatives have been prepared. Alkylation sites have been determined by 2D NMR techniques and for three compounds have been confirmed by X-ray crystallography. The N-9/N-3 regioselectivity can be justified by the electronic effects of the substituents at positions 2 and 6 of the purine. 2014-05-23T07:11:50Z 2014-05-23T07:11:50Z 2014 info:eu-repo/semantics/article García-Rubiño, M.E.; et al. Stereospecific alkylation of substituted adenines by the mitsunobu coupling reaction under microwave-assisted conditions. RSC Advances, (2014). [http://hdl.handle.net/10481/31881] 2046-2069 http://hdl.handle.net/10481/31881 10.1039/C4RA01968G eng http://creativecommons.org/licenses/by-nc-nd/3.0/ info:eu-repo/semantics/openAccess Creative Commons Attribution-NonCommercial-NoDerivs 3.0 License Royal Society of Chemistry