3- methyl-l- pentyn

The alkane formed by hydrogenation of (S)-4-methyl-l-hexyne is optically active, but the one formed by hydrogenation of (S)-3-methyl-l-pentyne is not. Explain. Would you expect the products of hydrogenation of these two compounds in the presence of Lindlar palladium to be optically active ... 

The alkane formed by hydrogenation of (5 )-3-methyl-l-pentyne is achiral it cannot be optically active. 

FIGURE 42 Comparison of mean initial activities per unit silica volume (ry jio ) for the selective hydrogenation of 3-methyl-l-pentyn-3-ol (A) and mean maximum yields of the desired intermediate product 3-methyl-l-penten-3-ol in the hydrogenation of 3-methyl-l-pentyn-3-ol (B) averaged over several runs for the conversion catalyzed by acicular mullite with large pores, acicular mullite with small pores, and cordierite. Conditions hydrogen pressure 2.3 bar alkyne concentration 20 mol/m solvent, ethanol and temperature, 297.4 K. 

Hcxyne, 2-hexyne, 3-hexyne, 3-methyl-l-pentyne, 4-methyl-l-p ntyne, 4-methyl-2-pentyne, 3,3-diirethyl-l-butyne ... 

Ketones react with acetylide ion (Section 8.7) to give alcohols. For example, the reaction of sodium acetylide with 2-butanone yields 3-methyl-l-pentyn-3-ol ... 

Pd(OAc)2 (47.35 % Pd) was purchased from Degussa. The compounds 4-iodo-toluene, n-butyllithium (1.6 M in hexane), 3-methyl-l-pentyn-3-ol, 2-butyne-l,4-diol, phenylacetylene, diphenylacetylene, 1-ethynyl-l-cyclohexanol and 2-methyl-... 

Both the activity and selectivity of all catalysts batches were tested in the hydrogenation of 3-methyl-l-pentyn-3-ol before use. 

Under normal conditions these compounds are stable and do not decompose. Most of these are noncombustible substances. Only 2-methyl-3-butyn-2-ol and 3-methyl-l-pentyn-3-ol are flammable liquids [flash point (open cup) 25° (77°F) and 38°C (100.4°F), respectively]. 

Methyl-l -pentyn-3-ol OH Liquid bp 121.4°C In the production of Moderately toxic ... 

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