Department Chemie, Ludwig-Maximilians-Universität München, Butenandtstrasse 5-13, Haus F, 81377, München, Germany.
Chemistry. 2020 Jul 22;26(41):8951-8957. doi: 10.1002/chem.202000870. Epub 2020 Jun 29.
Chiral β-aminoalkylzinc halides were prepared starting from optically pure commercial β-amino-alcohols. These amino-alcohols were converted to the corresponding N-pyrrolyl-protected alkyl iodides which undergo a zinc insertion in the presence of LiCl (THF, 25 °C, 10-90 min). Subsequent Negishi cross-coupling or acylation reactions with acid chlorides produced amino-derivatives with retention of chirality. Diastereoselective CBS-reductions of some prepared N-pyrrolyl-ketones provided 1,3-subsituted N-pyrrolyl-alcohols with high diastereoselectivity. Additionally, a deprotection procedure involving an ozonolysis allowed the conversion of the pyrrole-ring into a formamide without loss of optical purity.
手性β-氨基烷基卤化物可由光学纯的商业β-氨基醇起始制备。这些氨基醇被转化为相应的 N-吡咯基保护的烷基碘化物，它们在 LiCl（THF，25°C，10-90 分钟）存在下进行锌插入反应。随后与酰氯进行 Negishi 交叉偶联或酰化反应，保留了手性的氨基酸衍生物。一些制备的 N-吡咯基酮的 CBS-不对称还原提供了具有高非对映选择性的 1,3-取代的 N-吡咯基醇。此外，涉及臭氧分解的脱保护程序允许将吡咯环转化为甲酰胺，而不会损失光学纯度。
