A new synthesis of vitamin C

l-Arabinose was reduced to l-arabinitol and condensed with formaldehyde to give two bis(di-0-methylene-l-arabityloxymethane and two di-O-methylene-l-arabinitol derivatives. Cis-fused 1,3:2,4-Di-O-methylene-l-arabinitol and trans-fused 2,4:3,5-Di-O-methylene-l-arabinitol were also isolated; only the former was affected by the oxidation to give the corresponding aldehyde, which was converted successively to the hydroxy amide, the ethyl hydroxy ester, the corresponding keto ester and vitamin C.