10.8 When 3,3-dichloropentane is treated with excess sodium amide in liquld ammonia the initial product is 2-pentyne H H H HHCIHH xs NaNH2 H-C-C-C-C-C-H H-Č-Č-CEC-C-H NHa ( H H H H CIH H However, under these conditions, this internal alkyne quickly isomerizes to form a terminal alkyne that is subsequently deprotonated to form an alkynide ion
HHH HHH xs NaNH2 H-C-C-c-c=c? H H xs NaNHp H-O-O-CEC-C-H H-C-C-C-CEC-H NHa ( NHa ( HH H HH H H H H The isomerization process is believed to occur via a mechanism with the following six steps (1) deprotonation, (2) resonance, (3) protonation, (4) deprotonation, (5) resonance, (6) protonation Using these six steps as a guide, try to draw the mechanism for isomerization. Explain why the equilibrium favors the terminal alkyne