Why does Cl- get eliminated from a trichloromethyl anion to give dichlorocarbene? [closed]








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In the formation of dichlorocarbene, sodium trochloroacetate (in tetrachloroethene) is refluxed at 130 deg C resulting in decarboxylation which forms a trichloromethyl anion. (Does this step happen because of the increase in entropy? What is the driving force for this step?) Alpha elimination of Cl- then occurs to give dichlorocarbene but as carbenes are so unstable surely this final step would be energetically unfavourable? Why does it still happen? Is it just because the reaction is being heated? Does this provide enough energy for this step to happen? Is this step in equilibrium?


