First synthesis of 4a-carba-β-d-galactofuranose

The synthesis of 4a-carba-β-d-galactofuranose is described starting from diacetone glucose. The key ring-closure step was carried out by metathesis to form a cyclopentene. Catalytic hydrogenation of the CC double bond gave the galacto configured saturated carbahexofuranose with excellent diastereoselectivity.