Cyano-2-phenylacetylene

Terminal acetylenes such as phenylacetylene are transformed by Znl2, CuCl, CuBr, or CuCN and BTSP 1949 into 1-iodo- 1976, 1-chloro- 1978, 1-bromo- 1979, or l-cyano-4-phenylaIkynes 1980 and to the diacetylene 1977 [156] (Scheme 12.44). 

Diazo-substituted 1,2,3-triazoles undergo regiospecific dipolar cycloaddition reactions with electron-rich unsaturated compounds. Thus, 4-diazo-5-phenyl-4//-1,2,3-triazole (272, R = Ph) reacts with 1 -morpholinyl-2-nitroethene (273) in CH2CI2 at 20 °C by a net 1,7-cycloaddition and elimination of morpholine to give the product (274) (Scheme 53). 4-Diazo-5-cyano-4/f-1,2,3-triazole (272, R = CN) similarly adds to phenylacetylene to form compound (275) <87JOC5538>. 

Condensation, of paraldehyde with diethyl malonate, 32, 54 of a-phene thyl chloride with diphenylacetonitrile, 39, 74 of phenylacetylene with ethyl orthoformate, 39, 59 of 1-phenylbiguanide with ethyl chloroacetate, 38,1 of potassium diphenylacetonitrile with benzyl chloride, 39, 73 of potassium trithiocarbonate with potassium chloroacetate, 39, 77 of sodium acetylacetonate to tetraacetylethane, 39, 61 of sodium formylacetone with cyano-acetamide, 32, 32 of tetracyanoethylene with N,N-dimethylaniline, 39, 68 of thiophene, paraldehyde, and hydrogen chloride, 38, 86 of thiourea with furfuryl alcohol, 36,66... 

Both pyrrole itself, as well as 4,5,6,7-tetrahydroindole underwent N-vinylation with 2-cyano-l-phenylacetylene in DMSO in the presence of KOH, while the treatment of 4,5,6,7-tetrahydroindole with 2-benzoyl-1-phenylacetylene under the same conditions furnished predominantly a C-vinylated product <03S1272>, Several functionalized 3-vinylpyrroles were prepared by reaction of pyrrole-3-carbodithioates with malonitrile, cyanacetamide, or ethyl cyanoacetate induced by KOH in DMSO <03TL3501>. 

In a search for new isoxazole-based liquid crystalline compounds, a 22-member library of 3,5-diaryl isoxazoles 628 was prepared by parallel synthesis on solid phase (Rink resin) through 1,3-dipolar cycloaddition of supported phenylacetylene units with suitable aryl nitrile oxides generated in situ from hydroxyiminoyl chlorides. Cleavage from the resin under acidic conditions allowed the generation of the cyano moiety <2004TL2277>. 

When the reaction with propargyl alcohol is run in an amine solution at elevated temperature, the alkynylated product first formed is further transformed by a cyclization reaction with the pyridine nitrogen 3-piperidinoindolizine (35) is formed (36% yield) in piperidine at 80°C. Corresponding cyclization products result from the reaction with 1-bromoisoquinoline or 2-bromoquinoline with propargyl alcohol (80BCJ3273). Alkynylation (38) of 2-chloro-, 3-bromo-, and 4-iodopyrimi-dines, which are vicinally substituted by a cyano, carbamoyl, or ethoxy-carbonyl group, has been effected with phenylacetylene by heating the... 

Sodiiim phenylacetylene, reaction with p-nitrophenyl-propiolyl chloride, 615 Stilbazoles, -carboxy-prep-aration from pyridine aldehydes, 342, 343 stereochemistry, 342, 343 -cyano-preparation from pyridine aldehydes, 343 stereochemistry, 343 stereochemistry of, 348, 349 synthesis, 348, 349 Strecker reaction, preparation of 2-cyanomethylfurans, 666 Strecker synthesis, of pyri-dine-side chain nitriles, 362, 535-538 Streptonigrin, 626 Styryl isocyanates, reaction with ynamines, 639 6-Substituted-2,4-bis(alky 1-... 

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