Methyl ethynyl

C-NMR spectroscopic studies on a-substituted tris(ethynyl)methyl cations 49 prepared from alcohols 50 (equation 18) provided evidence for the participation of resonance structures with allenyl cationic character38. The parent tris(ethenyl)methyl cation (49, R = H) cannot be generated under stable carbocation conditions (SbFs/FSOsH) presumably due to the highly reactive unsubstituted termini of the three ethynyl groups and the resulting low kinetic stability. The chemical shift data (Table 1) give evidence that in all cases Ca and CY are deshielded more than Cg (relative to their precursor alcohols). 

TABLE 1. 13C-NMR Chemical Shifts of Tris(ethynyl)methyl Cations (49a-d) and Their Precursor Alcohols 50a-d°... 

Ethynyl methyl ether -10 H30+ (buffer) Stamhuis and Drenth, ... 

A 1,6-silyl migration from N to O was postulated in the reaction of N,N -bis(trimethyl-silyl)aminophosphine 333 with ethynyl methyl ketone 334 (equation 204)471. 

Ethynyl methyl telluriums are prone to losing ethynyl groups in protic media. The main products of these reactions are acetylenes. 

Ethynyl methyl ether, see Methoxyacetylene, 1146 Ethynyl vinyl selenide, 1449... 

To the ketene silyl (thio)acetal (1 equiv.) was added at room temperature neat ethyl propynoate, dimethyl acetylenedicarboxylate or ethynyl methyl ketone (1 equiv.). The mixture was stirred for 5 h at room temperature. The volatile products were removed at room temperature in vacuo (0.1 Torr) for 30 min. Purification of the crude reaction mixture by silica gel column chromatography (ethyl acetate-hexane, 5 95) afforded cycloadducts. 

In the reactions between diethyl hydrogenphosphonate and indantrione or 2-benzyli-deneindan-1,3-dione, the former substrate yields phosphate adducts,but in the latter case, addition affords the phosphonate 203 The additions of hydrogenphosphonic diesters to propynal and ethynyl methyl ketone and to the ketones RC=CCOMe (R = Me or Ph) ", give 1,2-adducts. 

Ethyl nitroacetate methyl nitronate and ethynyl methyl ketone mixed with icecooling, and stored 2 days aziridine derivative. Y 82.1%. F. e. s. V. A. Tarta-kovskii, O. A. Lukoyanov, and S.S. Novikov, Dokl. Akad. Nauk SSSR 178 (h) 123 (1968) C. A. 69, 18948. 

Synonyms 2-Ethinylbutanol-2 Ethinylmethylethyl carbinol 3-Ethylbutinol 3-Ethylbutynol Ethyl ethynyl methyl carbinol... 

Ethyl linoleate 5178 Ethynyl methyl ketone 1686 2-Furfuryl methyl ketone 5496... 

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