NEET levelSingle correct optionDifficulty 1 of 3ro002
Hydrogenation of CHX3−C≡C−CHX3 with HX2 over Lindlar catalyst gives mainly
Acis-but-2-ene
Btrans-but-2-ene
Cbutane
Dbut-1-ene
Answer: A
Lindlar catalyst (Pd on CaCOX3, poisoned with quinoline) stops at the alkene stage and delivers both hydrogens to the same face (syn addition), so the cis alkene is formed.