Palladium-catalysed carbonyl allylations by mixed (E)- and (Z)-1,3-dichloropropene with SnI2-Bu4NI and SnCI2 diastereoselectively produce syn and anti 1-substituted 2-chlorobut-3-en-1-ols, respectively. These are transformed into cis and trans 1-substituted 2-vinyl epoxides.