Question
Identify the reagent from the following list which can easily
distinguish between 1 - butyne and 2 - butyne
A.
bromine, $$CC{l_4}$$
B.
$${H_2}$$ Lindlar catalyst
C.
dilute $${H_2}S{O_4},HgS{O_4}$$
D.
ammonical $$C{u_2}C{l_2}$$ solution
Answer :
ammonical $$C{u_2}C{l_2}$$ solution
Solution :
In 1 - butyne terminal hydrogen is acidic where as in 2 -butyne there is no terminal hydrogen. Thus 2 - butyne will not react with ammonical $$C{u_2}C{l_2}.$$ While 1 - butyne, being terminal alkyne, will give red ppt. with ammonical cuprous chloride