Pseudoacids. I. 4- and 5-Oxoacids
作者:E. J. Valente、J. F. Fuller、J. D. Ball
DOI:10.1107/s010876819701149x
日期:1998.4.1
commonly occur in compounds with proximate carboxylic acid and carbonyl (aldehyde or ketone) functions for the formation of five- or six-membered rings. Examples include trans-2,3-disubstituted aliphatic, (Z)-2,3-olefinic and o-disubstituted aromatic acids. Crystal structures of compounds in these categories are reported: trans-4-methyl-3-oxo-6-hydroxytetrahydropyran-3-carboxylic acid (6), monoclinic,
某些4-和5-含氧酸可能以环状环丙醇(或假酸)形式存在。这些通常存在于具有最接近羧酸和羰基(醛或酮)功能的化合物中,以形成五元或六元环。实例包括反式-2,3-二取代的脂族酸,(Z)-2,3-烯烃和邻二取代的芳族酸。报告了这些类别化合物的晶体结构:反式-4-甲基-3-氧代-6-羟基四氢吡喃-3-羧酸(6),单斜晶,C2 / c,a = 25.412(5),b = 6.291(1 ),c = 10.757(2)A,β= 104.84(3)度;青霉酸(7),4-甲氧基-5-羟基-5-(2'-丙烯基)二氢呋喃-2-酮,四方,P4(2)/ n,a = b = 15.83(2),c = 7.016( 11)A;粘氯酸(8),(Z)-3,4-二氯-5-羟基二氢呋喃-2-酮,三斜晶系,P1,a = 6.227(5),b = 8.085(5),c = 12.369(9)A, alpha = 99。50(5),β=