Synthesis of carbamates from diethoxycarbonyl hydrazine derivatives by E1cB eliminative cleavage of the N-N'-bond rather than reduction.

Treatment of diethoxycarbonyl hydrazine derivatives with methyl bromoacetate/Cs(2)CO(3)/MeCN at 50 degrees C followed by heating to 80 degrees C resulted in N-N' bond cleavage to the corresponding carbamates.