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By taking advantage of the solubility and reactivity of alkali-metal acetylides in liquid ammonia a widely applicable method has been developed for the preparation of acetylenic carbinols as well as glycols (1). The synthetic application of acetylenic carbinols as intermediates has been therefore very broad (1-3).However, the syntheses of analogous heterocyclic compounds has received little attention. Continuing our studies on the chemistry of heterocyclic compounds the syntheses of acetylenic carbinols, ketones, and their addition as well as condensation products has been carried out.The thiophene aldehydes used and ß-2-thienylacrolein were prepared according to earlier methods (4, 5). The sodium acetylide in liquid ammonia was prepared according to two methods (6a, b). The loss of liquid ammonia by evaporation was diminished and a better control of sub-zero temperatures was obtained by using a Dry Ice-acetone bath. The reaction mixtures were hydrolyzed either with dilute sulfuric acid or ammonium chloride. The yields of the carbinols were slightly greater with the latter.The yields of the carbinols (Ilia, b) were from 50-60%. Only with lower temperatures (-50°) and employing a higher dilution of ß-2-thienylacrolein, were the yields of 1 -(2-thienyl)-1 -pentene-4-yn-3 -ol (IIIc) as high as 30%.The yield of the analogous styrylethynylcarbinol was reported as 2% ( 7).The 2-thienylethynylcarbinol and 3-methyl-2-thienylethynylcarbinol are stable yellowish viscous oils which give rise to the characteristic silver and copper acetylene salts.The major application of acetylenic carbinols, prepared by condensations with a, /3-unsaturated carbonyl compounds, has arisen from the anionotropic rearrangement which has been extensively investigated (1): RCH=CHCH(OH)C=CH -RCH(OH)CH=CHC=CH, where R = an alkyl group. SUMMARY 1. Three new acetylenic carbinols were synthesized from the corresponding thiophene aldehydes using sodium acetylide in liquid ammonia.2. The carbinols obtained were oxidized to the corresponding ketones with chromic acid in acetone.3. The acetylenic ketones were condensed with ammonia and amines to give the expected thiophene pyridines and pyrimidines.

Previous attempts to synthesize thienylacetylenes by standard procedures have resulted in anomalous reactions (1,2) or in extremely low yields (3). The present study discloses a new method involving dehydrohalogenation of 2-(l, 1dichloroethyl)thiophene or 2-(1-chlorovinyl)thiophene with sodium amide in liquid ammonia. Yields as high as 65 % have been obtained when aniline is employed in catalytic quantities. As starting material for this preparation the readily available 2-and 3-acetothienones were chosen, which were prepared as heretofore. SUMMARY Sodium amide in liquid ammonia was successfully applied in the thiophene series for the formation of the triple bond from 2-(l, l-dichloroethyl)thiophene, 2-(1 -chlorovinyl)thiophene, and corresponding substituted derivatives as well as from 2-(2-bromovinyl)thiophene. The yields were as high as 60-80%. Four new thienylacetylenes were synthesized. New York 58, . Y.

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