Tetrahedron letters

A new practical method for the synthesis of unsymmetrical ureas via high-pressure-promoted condensation of 2, 2, 2-trichloroethyl carbamates (Troc-carbamates) with …

S Azad, K Kumamoto, K Uegaki, Y Ichikawa, H Kotsuki

Index: Azad, Saleha; Kumamoto, Koji; Uegaki, Kaoru; Ichikawa, Yoshiyasu; Kotsuki, Hiyoshizo Tetrahedron Letters, 2006 , vol. 47, # 4 p. 587 - 590

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Citation Number: 23

Abstract

Troc-carbamates 1 were readily prepared from amine precursors by conventional treatment with 2,2,2-trichloroethyl chloroformate. 12 Since these Troc-protected amines are only weakly activated, it is not surprising that there are only a few reports on the use of these substrates for the synthesis of ureas. 10c, 10h and 13 We thought that at high pressure the desired reactions should proceed smoothly without the use of any catalysts or additives, since ...