Non-enzymatic diastereoselective asymmetric desymmetrization of 2-benzylserinols giving optically active 4-benzyl-4-hydroxymethyl-2-oxazolidinones: asymmetric syntheses of α-(hydroxymethyl)phenylalanine, N-Boc-α-methylphenylalanine, cericlamine and BIRT-377
作者:Shigeo Sugiyama、Satoshi Arai、Keitaro Ishii
DOI:10.1016/j.tet.2012.06.090
日期:2012.9
diastereoselective asymmetric desymmetrization process. Debenzylation of (4R)-5a using trifluoromethanesulfonic acid and anisole in MeNO2 gave (R)-4-benzyl-4-hydroxymethyl-2-oxazolidinone (R)-15a, which was converted into (R)-(α-hydroxymethyl)phenylalanine (7) in two steps. N-Boc-α-methylphenylalanine (8), cericlami0ne (9) and BIRT-377 (10) were also synthesized using these asymmetric desymmetrization
(S)-2-苄基-2-(α-甲基苄基)氨基-1,3-丙二醇(S)-4a与氯甲酸2-氯乙酯的反应,随后加入DBU得到(4R,αS)通过非对映选择性不对称脱对称过程,-4-苄基-4-羟甲基-3-(α-甲基苄基)-2-恶唑烷酮(4 R)-5a(92%de)。使用三氟甲磺酸和苯甲醚在MeNO 2中对(4 R)-5a进行脱苄基反应得到(R)-4-苄基-4-羟甲基-2-恶唑烷酮(R)-15a,将其转化为(R)-(α-羟甲基)苯丙氨酸(7)分两步进行。N - Boc -α-甲基苯丙氨酸(8),cericlamine(9)和BIRT-377(10)也使用这些不对称脱对称和脱苄基反应合成。