以天然手性产物L-脯氨酸为原料,经酯化、氨基保护和格氏反应,得到一种新型光学活性的脯氨醇衍生物((S)-N-苄基-2-吡咯烷-α,α-二(α-萘基)甲醇1).1经过催化氢解,得到另一种光学活性脯氨醇衍生物((S)-2-吡咯烷-α,α-二(α-萘基)甲醇2).将1和2作为有机催化剂,用于催化二烷基锌和醛的不对称加成反应.分别考察了影响对映选择性的催化剂结构、催化剂用量、溶剂、反应温度等各种因素.结果表明,当催化剂用量为5%、溶剂为甲苯、反应温度为-10℃,1作催化剂时,所得仲醇的对映体过量达82%ee,产率高达100%.
A new (S)-prolinol derivative , (S)-( N)-benzyl-2-( di-ot-naphthylhydroxyl methyl)pyrrolidine 1, using L-proline as raw material, was synthesized by a three-step process which were esterization, protection of amino-group and Grignard reaction. The other one, (S) -2-(di-α-naphthylhydroxymethyl) pyrrolidine 2, was obtained by catalytic hydrogenolysis from 1. They have been used as chiral catalysts in the asymmetric addition of diethylzinc to aldehydes. The effects of the amount of catalysts, the structure of catalysts , solvent and reaction temperature on enantioselectivity were also studied. When the amount of catalyst was 5% relative to aldehyde , solvent was toluene and reaction temperature was - 10 ℃, the chiral β-amino alcohol 1, has been successfully applied in the catalytic enantioselective addition of diethylzinc to aldehydes to give sec-alcohols in good to high yields with up to 82% enantiomeric excesses.