Tatyana E. Glotova

1,3-Dipolar Cycloaddition of 3-Phenylamino-5-phenylimino- 1,2,4-dithiazole to 1-Acyl-2-phenylacetylenes—A New Route to Functionalized 1,3-Thiazole Derivatives

Abstract3-Phenylamino-5-phenylimino-1,2,4-dithiazole reacted with 1-acyl-2-phenylacetylenes in ethanol or toluene on heating (78–80°C, 1 h) in chemo- and regioselective fashion to give previously unknown N-[5-acyl-3,4-diphenyl-1,3-thiazol-2(3H)-ylidene]-N′-phenylthioureas (yield 57–60%). The structure of N-[5-benzoyl-3,4-diphenyl-1,3-thiazol-2(3H)-ylidene]-N′-phenylthiourea was proved by X-ray analysis.

Chemo- and Regiospecific Monoaddition of Secondary Phosphine Sulfides to 1-Acyl-2-phenylacetylenes

Secondary phosphine sulfides react with 1-acyl-2-phenylacetylenes under mild conditions (KOH, THF, r.t.) to afford chemo-and regiospecifically 3-diorganophosphorothioyl-1-R-3-phenyl-2-propen-1-ones in high yield, with the E-isomers being formed exclusively (R = Ph and 2-thienyl) or predominantly (60%, R = Me).

Reaction of secondary phosphine oxides with acylacetylenes

Secondary phosphine oxides reacted with 1-alkanoyl-2-phenylacetylenes in chemoselective fashion under mild conditions (20°C, THF) in the absence of a catalyst (diphenylphosphine oxide) or in the presence of potassium hydroxide [bis(2-phenylethyl)phosphine oxide] to give 1-alkyl-1-diphenyl(or 2-phenylethyl)-phosphoryl-3-phenylprop-2-yn-1-ols in up to 96% yield. The reaction of diphenylphosphine oxide with 1-alkanoyl-2-phenylacetylenes in the system KOH-THF (20°C) afforded not only adducts at the carbonyl group but also products of double α,β-addition at the triple bond, 2,3-bis(diphenylphosphoryl)-3-phenylpropan-1-ones.

One-pot assembly of 3,5-bis(1H-pyrrol-2-yl)-4H-1,2,4-triazol-4-amines from pyrrolecarbo-nitriles and hydrazine

The reaction of pyrrole-2-carbonitriles with hydrazine hydrate in the presence of hydrazine dihydrochloride (ethylene glycol, 130-132°С, 1-2 h, argon atmosphere) affords the hitherto unknown 3,5-bis(1H-pyrrol-2-yl)-4H-1,2,4-triazol-4-amines in up to 86% yield.

New 1,3,4-thiadiazole derivatives from 1-benzylidenethiocarbonohydrazides and 3-Bromo-1-phenylprop-2-yn-1-one

Abstract3-Bromo-1-phenylprop-2-yn-1-one reacted with 1-benzylidenethiocarbonohydrazones in acetic acid or acetonitrile at room temperature (reaction time 3 h) to give in good yields the corresponding benzaldehyde N′-(5-benzoylmethyl-1,3,4-thiadiazol-2-yl)hydrazone hydrobromides which were converted into the free bases by treatment with aqueous ammonia.

Reaction of N-(carbamimidoyl)thiourea with 1-benzoyl-2-phenylacetylene

Abstract1-Benzoyl-2-phenylacetylene reacted with N-(carbamimidoyl)thiourea in glacial acetic acid saturated with 20% HBr to give (4,6-diphenyl-2H-1,3-thazin-2-ylidene)guanidine hydrobromide. The reaction of the same compounds in anhydrous ethanol in the presence of sodium ethoxide led to the formation of N-(4,6-diphenylpyrimidin-2-yl)thiourea. Bis(3-oxo-1,3-diphenylprop-1-en-1-yl) sulfide and 1-benzoyl-2-ethylsulfanyl-2-phenylethylene were isolated in the reactions of 1-benzoyl-2-phenylacetylene with N-(carbamimidoyl)thiourea and N-(carbamimidoyl)-S-ethylisothiuronium bromide, respectively, in anhydrous methanol.

NEW FUNCTIONALIZED PYRAZOLINES FROM 1-AROYL-2-PHENYLACETYLENES AND THIOCARBONOHYDRAZIDES

The reaction of 1-aroyl-2-phenylacetylenes with thiocarbonohydrazide and benzaldehyde thiocarbohydrazone in acetic acid-water or ethanol-water systems with the reagents in an equimolar ratio leads to the selective formation of 1-carbothiohydrazinoyl-5-hydroxy-3-phenyl-5-R-2-pyrazolines. Ring-chain tautomerism involving the enamine and hydrazone forms was detected for solutions of the pyrazolines (with R = 2-thienyl) in DMSO.

Synthesis and steric structure of N″-(arylmethylidene)-N″′-(1-methyl-3-phenylprop-2-yn-1-ylidene)thiocarbonohydrazides

Thiocarbonohydrazones derived from aromatic aldehydes reacted with 4-phenylbut-3-yn-2-one in aqueous acetic acid (20°C, 2 h) to produce previously unknown N″-[(E-s-cis)-arylmethylidene]-N″′-[(Z-s-trans)-1-methyl-3-phenylprop-2-yn-1-ylidene]thiocarbonohydrazides with high chemo-, regio-, and stereoselectivity. The steric structure of N″-[(E-s-cis)-benzylidene]-N″′-[(Z-s-trans)-1-methyl-3-phenylprop-2-yn-1-ylidene]thiocarbonohydrazide in crystal and in solution was studied by X-ray analysis and IR and NMR spectroscopy.