ISSN print edition: 0366-6352
ISSN electronic edition: 1336-9075
Registr. No.: MK SR 9/7
Palladium-catalysed Claisen rearrangement of 6-allyloxypurines
Petr Koukal, Hana Dvořáková, Dalimil Dvořák, and Tomáš Tobrman
Department of Organic Chemistry, Institute of Chemical Technology, Prague, Technická 5, 166 28 Prague 6, Czech Republic
Abstract: 6-Allyloxypurines readily undergo palladium-catalysed Claisen rearrangement under mild conditions affording N
1-substituted hypoxanthines. In contrast with the previously reported protocol, the Claisen rearrangement can be performed
using Pd(PPh3)4 or Pd(dba)2/dppf in dry THF at 60°C. The reaction can accommodate variously substituted allyl fragments to position N
1 of the hypoxanthine skeleton with high yields. Retention of the double bond configuration during rearrangement was observed.
Keywords: Claisen rearrangement – purine – allyloxypurines – palladium – hypoxanthine
Full paper is available at www.springerlink.com.
Chemical Papers 67 (1) 3–8 (2013)