Synthesis 2001(11): 1704-1710
DOI: 10.1055/s-2001-16765
PAPER
© Georg Thieme Verlag Stuttgart · New York

The Suzuki-Miyaura Cross-Coupling Reactions of 2-, 6- or 8-Halopurines with Boronic Acids Leading to 2-, 6- or 8-Aryl- and -Alkenylpurine Derivatives

Martina Havelkováa, Dalimil Dvořák*a, Michal Hocek*b
a Department of Organic Chemistry, Prague Institute of Chemical Technology, 16628 Prague 6, Czech Republic
Fax: +420(2)24354288; e-Mail: dvorakd@vscht.cz;
b Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, 16610 Prague 6, Czech Republic
Fax: +420(2)3111271; e-Mail: hocek@uochb.cas.cz;
Further Information

Publication History

Received 25 April 2001
Publication Date:
28 September 2004 (online)

Abstract

The Suzuki-Miyaura cross-coupling reactions of 9-benzyl-6-chloropurine, 9- or 3-benzyl-8-bromoadenine and 2,6-dihalopurines with boronic acids gave the corresponding 6-, 8- or 2-aryl- or -alkenylpurines in good yields. Anhydrous conditions in toluene were superior for coupling of electron-rich boronic acids, while aqueous DME was used for electron-poor arylboronic acids as well as for alkenylboronic acids. A good regioselectivity was observed for the coupling of 2,6-dihalopurines: 9-benzyl-2,6-dichloropurine reacted with one equivalent of phenyl boronic acid to give 9-benzyl-2-chloro-6-phenylpurine, while an analogous reaction of 9-benzyl-6-chloro-2-iodopurine gave selectively 9-benzyl-6-chloro-2-phenylpurine.