A process for preparing a compound of the formula ##STR1## wherein R and R.sup.1 independently are selected from hydrogen and C.sub.1 -C.sub.4 alkyl groups, which comprises catalytically hydrogenating a compound of formula ##STR2## wherein R and R.sup.1 are as defined above and X is halogen using platinum oxide as catalyst.
制备化合物的过程的公式##STR1##其中R和R.sup.1独立地从氢和C.sub.1-C.sub.4烷基基团中选择,包括使用
铂氧化物作为催化剂催化氢化具有公式##STR2##其中R和R.sup.1如上定义,X是卤素的化合物。