High-Yield Synthesis of 20-, 24-, and 28-Membered Macropentolide, -hexolide, and -heptolide, Respectively, from (<i>R</i>)- or (<i>S</i>)-3-hydroxybutanoic acid under<i>Yamaguchi</i>'s macrolactonization conditions
作者:Dieter Seebach、Urs Brändli、Peter Schnurrenberger、Michael Przybylski
DOI:10.1002/hlca.19880710119
日期:1988.2.3
oligomers formed in ca. 50% yield from enantiomerically pure 3-hydroxybutanoic acid under Yamaguchi's macrolactonization conditions. The FAB mass spectra of the MH+, M Na+, and MCs+ are reported (Figs. 2, 3, 5, and 6). No cyclic tetramer is detected. The 1H-NMR spectra of the cyclic oligomers, of the monomer, and of the polymer (PHB) are very similar (Fig. 4). Directed synthesis of the open-chain dimer and
大环戊内酯1,己内酯2和庚内酯3构成ca。形成在所述低聚物的80%约 在山口的大环内酯化条件下,对映体纯的3-羟基丁酸的收率为50%。报道了M H +,M Na +和M Cs +的FAB质谱图(图2、3、5和6)。未检测到环状四聚体。环状低聚物,单体和聚合物(PHB)的1 H-NMR谱图非常相似(图4)。3-羟基丁酸的开链二聚体和四聚体的直接合成和尝试的环化作用不会导致环状四聚体的分离。