A NOVEL MONOALKYLATION OF SYMMETRICAL ALPHA-DIONES

Citation
D. Gopal et al., A NOVEL MONOALKYLATION OF SYMMETRICAL ALPHA-DIONES, Tetrahedron letters, 39(14), 1998, pp. 1877-1880
Citations number
14
Categorie Soggetti
Chemistry Inorganic & Nuclear
Journal title
ISSN journal
00404039
Volume
39
Issue
14
Year of publication
1998
Pages
1877 - 1880
Database
ISI
SICI code
0040-4039(1998)39:14<1877:ANMOSA>2.0.ZU;2-0
Abstract
An efficient method has been developed for the synthesis of monoalkyla ted 1,2-diones by using steric approach control. The dihydropyrazine 2 prepared from 2,3-butanedione and 1,2-diamino-2-methylpropane is sele ctively deprotonated on the less hindered methyl group to give an anio n which is alkylated with alkyl iodides and activated bromides. In sit u hydrolysis of the alkylated dihydropyrazines gives monoalkylated dio nes 4 in good yield. (C) 1998 Published by Elsevier Science Ltd. All r ights reserved.