2,2,5,5,-Tetramethyl-3-hexyne

The kind of surface site catalyzing alkyne half-hydrogenation has been the subject of some speculation. Two possibilities are shown in Fig. 2.2. Certainly such a site should fit the evidence Burwell and associates obtained from the hydrogenation of di-tert-butyl acetylene (2,2,5,5-tetramethyl-3-hexyne). 31 They proposed that the molecule dislocated a surface atom, pulling it up out of the plane of the surface (Fig. 2.3). That work concluded that hydrogenation... 

Trimethylsilylphenylsilylene also reacts with disubstituted acetylenes such as 3-hexyne, 1-trimethylsilylpropyne, bis(trimethylsilyl)acetylene, and 2,2,5,5-tetramethyl-3-hexyne to give the respective silacyclopro-penes. The silacyclopropenes thus formed, with the exception of 1,2,3-tris(trimethylsilyl)-l-phenyl-l-silacyclopropene, can be distilled under reduced pressure without decomposition. 

Problem 11.21 Explain why 2,2,5,5-tetramethyl-3-hexyne can t be made using acetylide anions. 

Di-/i-chlorobis[(3,4-i )-2,2,5,5-tetramethyl-3-hexyne]bis(tri-chlorostannyl)diplatinuin, loci Di-fJL-chlorobis di-ieTi-butylethyne)bis trichloros-tannyl)diplatinum [75525-41-6]... 

Chlorodiphenylgermane, Ge-00149 Chloromethoxydimethylstannane, Sn-00031 Chloromethoxydimethyltin, see Sn-00031 (Chloromethyl)trichlorogermane, see Ge-00001 (Chloromethyl)trimethylgermane, Ge-00046 (Chloromethyl)trimethylstannane, Sn-00067 Chlorophenylgermylene, Ge-00065 ChIoro(7V,7V,7V, 7V -tetramethyl-1,2-ethanediamine-7V,yV )-(triphenylstannyl)cadmium, in Sn-00322 Chloro(2,2,5,5-tetramethyl-3-hexyne)(trichlorostannyl)platinum, in Sn-00357... 

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