Tetrahedron

Reactions of ketenes with ethoxyalkynes: Synthesis of 2, 2, 4-trialkylcyclobutane-1, 3-diones

CC McCarney, RS Ward, DW Roberts

Index: McCarney,C.C. et al. Tetrahedron, 1976 , vol. 32, p. 1189 - 1192

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Citation Number: 8

Abstract

Treatment of dimethyl ketene with ethoxyacetylene 1a, 1-ethoxyoct-1-yne 1b, and 1- ethoxytetrade-1-yne 1c afforded the 3-ethoxycyclobutenones 2a–c. Hydrolysis of 2a–c with dilute hydrochloric acid gave the cyclobutane-1, 3-diones 3a–c. The 1H NMR spectra of these compounds indicate that in CDCl3 solution 2, 2-dimethylcyclobutane-1, 3-dione 3a exists as the diketone, whereas the 2, 2, 4-trialkylcyclobutane-1, 3-diones 3b and 3c exist ...