. Can. J. Chem. 60,2295Chem. 60, (1982. Several syntheses of the previously unknown 1,2-dihydro-3H-pyrrolo[l,2-a]pyrrole-l-carboxylic acid and various 5-and 6-substituted derivatives thereof have been devised. Some of these processes have been extended to the heretofore unreported 5,6,7,8-tetrahydropyrrolo[l,2-a]pyridine-8-carboxylic acid and 5,6,7,8-tetrahydro-9H-pyrrolo[l,2-a]azepine-9-carboxylic acid derivatives.Two new processes were developed for the conversion of pyrroles into the corresponding pyrrol-2-acetic acid esters. Both processes were based on the use of the readily available ethoxalylpyrrole derivatives as the starting material. One sequence involved saponification of the a-keto ester, followed by Wolff-Kishner reduction of the crude a-keto acid salt and subsequent esterification of the acetic acid derivative thus produced. The second synthesis commenced with reduction of the 2-ethoxalpyrrole with sodium borohydride to the a-hydroxy ester, which was further reduced to the acetic acid ester with an equimolar mixture of triphenylphosphine and triphenylphosphine diiodide.

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The synthesis of a number of trisubstituted allenyl steroids is reported. Reaction of N-(Z-chloro-l,l,Z-tri-fluoroethy1)diethylamine on difluorocyclopropenylcarbinols is shown to be a convenient route to trifluoromethylallenes. Chlorotrifluorotriethylamine reacts stereoselectively with cyclopropenonylcarbinols to provide allenic acid fluorides in high yield. Allenic acid fluorides are easily converted into p-keto esters. The structure and stereochemistry of the novel steroidal allenes are based on their chemical and spectroscopic properties. (6) (a) N. N. Yarovenko and M . A. Raksha, Zh. Obshch. Khim., 29, 2159 (1959); Chem. Abatr., 64, 9724h (1960); (b) D. E. Ayer, Tdrahedron Lett., 1065 (1962); (e) L.