18-Membered cyclic esters derived from glycolide and lactide: preparations, structures and coordination to sodium ions
作者:Malcolm H. Chisholm、Judith C. Gallucci、Hongfeng Yin
DOI:10.1039/b709081a
日期:——
From reactions between glycolide or lactide (4 equiv.) with 4-dimethylaminopyridine, DMAP (1 equiv.) and NaBPh(4) (1 equiv.) in benzene at 70 degrees C the cyclic ester adducts (CH(2)C(O)O)(6)NaBPh(4) and (CHMeC(O)O)(6)NaBPh(4) are formed respectively. The structures of the salts Na[(S,R,S,R,S,R)-(CH(3)CHC(O)O)(6)](2)BPh(4).CH(3)CN and (CH(2)C(O)O)(6)NaBPh(4).(CH(3)CN)(2) are reported. The cyclic esters
由乙交酯或丙交酯(4当量)与4-二甲氨基吡啶,DMAP(1当量)和NaBPh(4)(1当量)在苯中于70°C下反应制得的环状酯加合物(CH(2)C(O分别形成)(O)(6)NaBPh(4)和(CHMeC(O)O)(6)NaBPh(4)。Na [(S,R,S,R,S,R)-(CH(3)CHC(O)O)(6)](2)BPh(4).CH(3)CN和据报道(CH(2)C(O)O)(6)NaBPh(4)。(CH(3)CN)(2)。通过色谱分离环状酯和(CH(2)C(O)O)(6),(S,R,R,R,R,R)-(CHMeC(O)O)(6)的结构和(S,S,R,R,R,R)-(CHMeC(O)O)(6)被确定。报告了(CHMeC(O)O)(6)的六个对映异构体之一和两个内消旋异构体的(1)H和(13)C NMR数据。根据DMAP和NaBPh(4)在产生NaPh和DMAP的热苯中的初始反应,讨论了形成这些