Unexpected pathway of the reaction of N-[(β-halogeno-α-tosyl)alkyl]ureas with β-oxoester enolates. Synthesis of ethyl 5-ureido-4,5-dihydrofuran-3-carboxylates and N-carbamoylpyrrole-3-carboxylates
摘要:
Reaction of beta-halogeno-alpha-tosyl-substituted N-alkylureas with sodium enolates of beta-oxoesters proceeds predominantly via nucleophilic substitution of the halogen rather than the tosyl group followed by spontaneous cyclization to give ethyl 5-ureido-4,5-dihydrofuran-3-carboxylates. The latter are transformed into ethyl N-carbamoylpyrrole-3-carboxylates under acidic conditions. (C) 2010 Elsevier Ltd. All rights reserved.
BULLOCK E.; CARTER R. A.; COCHRANE R. M.; GREGORY B.; SHIELDS D. C., CAN. J. CHEM. <CJCH-AG>, 1977, 55, NO 5, 895-905
作者:BULLOCK E.、 CARTER R. A.、 COCHRANE R. M.、 GREGORY B.、 SHIELDS D. C.
DOI:——
日期:——
Unexpected pathway of the reaction of N-[(β-halogeno-α-tosyl)alkyl]ureas with β-oxoester enolates. Synthesis of ethyl 5-ureido-4,5-dihydrofuran-3-carboxylates and N-carbamoylpyrrole-3-carboxylates
作者:Nikolay N. Kurochkin、Anastasia A. Fesenko、Dmitry A. Cheshkov、Musa M. Davudi、Anatoly D. Shutalev
DOI:10.1016/j.tetlet.2010.10.162
日期:2011.1
Reaction of beta-halogeno-alpha-tosyl-substituted N-alkylureas with sodium enolates of beta-oxoesters proceeds predominantly via nucleophilic substitution of the halogen rather than the tosyl group followed by spontaneous cyclization to give ethyl 5-ureido-4,5-dihydrofuran-3-carboxylates. The latter are transformed into ethyl N-carbamoylpyrrole-3-carboxylates under acidic conditions. (C) 2010 Elsevier Ltd. All rights reserved.
ASHBY J.; GRIFFITHS D., J. CHEM. SOC. PERKIN TRANS. <JCPK-BH>, 1975, PART 1, NO 7, 657-662