A New Approach to Optically Active 1,2-Diaryl-1,2-diaminoethanes and 1,2-Diaryl-2-aminoethanols

高手性1，2-二芳基-1，2-二氨基乙烷和2-氨基-1，2-二甲醇作为手性助剂的广泛使用，加上与其制备相关的困难，促使我们研究其合成的新方法。为了制备这类化合物，本文研究了在（+）-间苯二酚磺酸为手性助剂的条件下，用Zn-Cu偶联对茴香基苯并亚胺进行对映体选择性的亚胺基蒎烯醇偶联，得到高对映体纯度的（R，R）-1，2-二苯基乙二胺衍生物。用0.5mol/ %的新的由L-苏氨酸衍生的恶唑硼烷和化学计量的BH_3THF对1，2-二（对甲氧基苯亚氨基）-1，2-二苯基乙二胺进行高对映选择性还原，得到对映体纯度高的1，2-二苯基乙二胺衍生物。随后除去氮原子得到对映体纯形式的（R，R）-1，2-二苯基乙二胺。此外，1，2-二芳基-2-苄氧基的还原 ...更多信息 用上述恶唑硼烷和BH_3Sme_2进行的苯乙酮反应，化学选择性地得到高对映体纯度的β-亚氨基醇。通过选择合适的还原条件，随后选择性还原亚氨基官能团得到高对映体纯度的顺式或反式2氨基-1，2-二芳基乙醇。在四氢呋喃（THF）中，用同样的恶唑硼烷和硼烷-THF络合物对1，3-二酮进行了高度非对映和对映选择性的还原，得到了高对映纯度的1，3-二醇。特别是环戊烷或环己-1，3-二酮衍生物的还原反应得到了手性1，3-二醇，它具有很好的对映体过量，而没有形成手性化合物。此外，在基本相同的条件下进行了内消旋酰亚胺的对映选择性还原，得到了高对映体纯度的羟基内酰胺。特别是，具有咪唑啉酮环的mes-imide的还原得到高对映体纯度的羟基内酰胺。由此得到的羟基内酰胺成功地转化为（+）-生物素。少

Widespread use of homoehiral 1,2-diaryl-1,2-diaminoethanes and 2-amino-1,2-dimylethanols as chiral auxiliaries coupled with difficulties associated with their preparation prompted us to investigate new methodologies for their syntheses. For the preparation of this highly useful class of compounds, enantioselecive imino pinaeol coupling of p-anisylbenzd-imine was investigated using Zn-Cu couple in the presence of (+)-camphorsulfonic acid as a chrial auxiliary to give (R,R)-1,2-diphenylethylemtediamine derivative in high enantiomeric purity. Highly enantioselective reduction of 1,2-bis(p-methoxyphenylimino)- 1,2-diphenylethmte was also conducted with 0.5 mo1% of new oxazaborolidine, derived from L-thronine and a stoichiomebic amount of BH_3THF, to give 1,2-diphenylethylenediamine derivative in excellent enantiomeric purity. The subsequent deportation of nitrogen atoms afforded (R,R)-1,2-diphenylethylenediamine in enantiomerically pure form. Moreover, the reduction of 1,2-diaryl-2-benzylo … More xyhnhtoethanones conducted using the above oxazaborolidine and BH_3 Sme_2 gave beta-imino alcohols chemoselectively in high enantiomeric purity. Subsequent selective reduction of the imino functionality affords either .syn- or anti-2amino-1,2-diarylethanols in high enantomeric purity by choosing appropriate reduction conditions. Highly diastereo- and enantioselective reduction of 1,3-diketones was also conducted using the same oxazaborolidine and borane-THF complex in THF to give 1,3-diols in high enamctiomeric purity. In particular, the reduction of cyclopentane or cyclohexan- 1,3-dione derivatives gave chiral 1, 3-diols it excellent enantiomericexcess without formation of mc.vo-compounds. Moreover, enantioselective reduction of meso-imide was conducted under essentially same conditions to give hydroxy lactams in highenantiomeric purity. In particular, the reduction of the mes-imide posssesing an imidazolidinone ring gave the hydroxy lactam with high enatiomeric purity. The hydroxy lactam thus obtained was successfully transfotmed into (+)-biotin. Less