The dimethyl and diethyl acetals of 4chlorobutyraldehyde and Cbromobutyraldehyde (1, l- dimethoxy-and 1, l-diethoxy-4-chlorobutane and 1, l-dimethoxy-and 1, l-diethoxy-4- bromobutane) are valuable synthetic intermediates. In particular, these acetals are useful in the Fischer indole synthesis of substituted tryptophols and tryptamines and in the synthesis of natural products.'Despite their utility and structural simplicity, there appears to be only ...