作者:Christián Di Nardo、Lucio O. Jeroncic、Rosa M. de Lederkremer、Oscar Varela
DOI:10.1021/jo960042z
日期:1996.1.1
obtained from 2 ( approximately 90% yield) as a mixture of the E and Z diastereoisomers, which were separated by column chromatography or, more efficiently, by HPLC. The catalytic hydrogenation of compounds 4-E and 4-Z took place diastereoselectively, due to the chiral induction of the stereocenter located in the lateral chain. Thus, hydrogenation of 4-E led to a mixture of the 4,5-dihydro-(3H)-furan-2-ones
用叔胺处理过-O-苯甲酰基-D-甘油-D-gulo-庚酮-1,4-内酯(2)(5H)-呋喃-2-一衍生物3,4,和5,分别通过控制消除1、2或3个苯甲酸分子而形成。通过NMR技术确定4和5的环外双键的立体化学。特别地,呋喃酮4是从2(约90%收率)作为E和Z非对映异构体的混合物获得的,其通过柱色谱法或更有效地通过HPLC分离。由于位于侧链的立体中心的手性诱导,化合物4-E和4-Z的催化氢化是非对映选择性的。因此,4-E的氢化导致具有3R,5S,2'S(D-木糖基)的4,5-二氢-(3H)-呋喃-2-酮的混合物 6)和3S,5R,2'S(D-arabino,7)配置,其中6为主要产品;而4-Z异构体给出的混合物相同,但优势为7。最初的4-E / Z混合物加氢后,重结晶后即可获得纯净的化合物6。6gave 9的O-脱苯甲酰化作用,用NaBH(4)还原为3,5-二脱氧-间-二甲苯基-庚醇(11)