CATALYTIC TRANSFER OF HYDROGEN .8. GAS OF REDUCING SUGARS

The catalytic hydrogen transfer of free anomeric sugars was studied with 2,3; 5,6-di-O-isopropylidene-d-mannofuranose and RuH//2(PPh //3)//4 as catalyst and extended to reducing sugars with other free hydroxyl groups. A regiospecific transfer converted these sugars into lactones in high yields with an excess of acceptor. Without acceptor, the free sugars were converted by a competititve oxidoreduction reaction into a mixture of lactone and itol.