4-Octyne → Octane

Participants

Reaction Conditions

Reaction Steps

An example of an alkene compound produced by partially hydrogenating an alkyne compound in the presence of a hydrogenation catalyst containing a hydrogenation promoter and a reducing agent will be described. First, 37.8 mg (1.00 mmol) of NaBH4 was charged to a 100-mL glass autoclave which was equipped with a stirrer and whose periphery was kept at 30° C., and the autoclave was purged with argon gas. Subsequently, 10 mL of DMF, 1.47 mL (10 mmol) of 4-octyne, and 1.00 mL (Pd content=10 μmol) of the hydrogenation promoter (1) prepared in Example 1 were added to the autoclave under an argon atmosphere. A hydrogenation catalyst (1) composed of the hydrogenation promoter (1) and NaBH4 was prepared in the autoclave by this operation. The autoclave was connected to a hydrogen gas cylinder via a gas-introducing tube, and air in the introducing tube was purged with hydrogen at 2 atm three times. Subsequently, hydrogen at 8 atm was introduced into the autoclave, and the hydrogen was then discharged carefully until the pressure was decreased to 2 atm. This operation was repeated seven times. The hydrogen pressure was then increased to 8 atm, and the solution was vigorously stirred at 30° C. Thereby, hydrogenation reaction proceeded. The conversion rate and the selectivity of cis-4-octene in the product were determined by GC. A trans isomer (trans-4-octene), positional isomers (trans-3-octene, cis-2-octene, and the like), and an excessively hydrogenated product (octane) were produced as by-products. Table 4 shows the result of this example. The selectivity described in Table 4 represents the ratio of the amount of cis isomer to the sum of all the amounts of alkenes (a cis isomer, a trans isomer, and positional isomers) and an alkane produced. This definition is also used for Table 5 and thereafter.

Provenance & Evidence