[Mo(H)(Cl)(P(CH3)3)3(N(C6H3(CH3CHCH3)2))] in benzene-d6 react. of HBCat with 0.4 M soln. of 3-hexyne (1:1 molar ratio) in C6D6 at temp. of 22°C for 24 h in presence of 5 molpercent of Mo complex as catalyst; detd. by NMR;