Asc. Chan et al., SYNTHESIS OF SPIRO[4.4]NONANE-1,6-DIOLS VIA THE HYDROGENATION OF SPIRO[4.4]NONANE-1,6-DIONE - THE PROFOUND EFFECT OF HYDROGENATING AGENTS, Tetrahedron : asymmetry, 6(12), 1995, pp. 2953-2959
The synthesis of spiro[4.4]nonane-1,6-diols via the catalytic as well
as stoichiometric hydrogenation of spiro[4.4]nonane-1,6-dione was stud
ied. Profound effects of the hydrogenation catalysts and reagents on t
he stereoselectivity of the products were observed. The choice of solv
ent also was found to have a significant influence on the product sele
ctivity. The opening of a spiro-ring in the starting material was iden
tified as a major side reaction in alcohol solvents. The absolute conf
iguration of the trans,trans-diol was unambiguously determined by Xray
crystallography.