Cardiff University | Prifysgol Caerdydd ORCA
Online Research @ Cardiff 
WelshClear Cookie - decide language by browser settings

Convenient synthesis of more complex 2-substituted 4(3H)-quinazolinones via lithiation of 2-alkyl-4(3H)-quinazolinones

Smith, Keith, El-Hiti, Gamal A., Abdel-Megeed, Mohamed F. and Abdo, Mohamed A. 1999. Convenient synthesis of more complex 2-substituted 4(3H)-quinazolinones via lithiation of 2-alkyl-4(3H)-quinazolinones. Collection of Czechoslovak chemical communications 64 (3) , pp. 515-526. 10.1135/cccc19990515

Full text not available from this repository.

Abstract

2-Methylquinazolin-4(3H)-one has been doubly lithiated, at nitrogen and in the 2-methyl group, with n-butylithium. The lithium reagent thus obtained reacts with a variety of electrophiles (iodomethane, D2O, phenyl isocyanate, benzaldehyde, benzophenone, cyclopentanone, 2-butanone, carvone) to give the corresponding 2-substituted derivatives in very good yields. Reaction of the dilithio reagent with acetonitrile gives an α,β-unsaturated imine by tautomerization of the initial addition product. Double lithiation of 2-ethyl- and 2-propyl-4(3H)-quinazolinones can be achieved using lithium diisopropylamide and the lithiated reagents thus obtained react with similar electrophiles to give the corresponding products in very good yields. In the reaction of the dianion of the 2-ethyl-4(3H)-quinazolinone with iodine, an oxidatively dimerised product was obtained. Lithiation of 2-unsubstituted 4(3H)-quinazolinone does not take place on C-2 under similar conditions.

Item Type: Article
Status: Published
Schools: Chemistry
Subjects: Q Science > QD Chemistry
Uncontrolled Keywords: Quinazolinones; Metallation; Double lithiation; Nucleophilic additions; Ketones; Carbanions
Publisher: Institute of Organic Chemistry and Biochemistry
ISSN: 0010-0765
Last Modified: 04 Jun 2017 02:51
URI: http://orca-mwe.cf.ac.uk/id/eprint/12695

Citation Data

Cited 20 times in Google Scholar. View in Google Scholar

Cited 22 times in Scopus. View in Scopus. Powered By Scopus® Data

Actions (repository staff only)

Edit Item Edit Item