3-乙氧羰基-2,3/2,5-二氢-1,5-苯并硫氮杂卓的互变异构及其热行为  

Tautomerism and thermal properties of 3-ethoxycarbonyl2,3/2,5-dihydro-1,5-benzothiazepines

作　　者：王丽娜[1] 邱召来[1] 张建军[2] 李媛[1] 

机构地区：[1]河北师范大学化学与材料科学学院,石家庄050024 [2]河北师范大学分析测试中心,石家庄050024

出　　处：《中国科学：化学》2013年第7期869-880,共12页SCIENTIA SINICA Chimica

基　　金：国家自然科学基金(20972040)资助

摘　　要：用核磁共振法研究了3-乙氧羰基-2,3/2,5-二氢-1,5-苯并硫氮杂卓(亚胺型杂卓4/烯胺型杂卓5)在氘代甲醇(CD3OD)、苯(C6D6)、三氯甲烷(CDCl3)和二甲基亚砜(DMSO-d6)四种不同极性溶剂中的互变异构.结果表明,无水条件下,亚胺型杂卓4和烯胺型杂卓5在非质子溶剂中不发生相互转化,而在质子溶剂中,亚胺型杂卓4不稳定,部分转化成其异构体—烯胺型杂卓5;基于杂卓4和5在DMSO和CHCl3中的紫外光谱有良好的区分度,用紫外光谱法研究了在DMSO及CHCl3(低温时)中溶液的温度、酸碱度对其互变异构的影响,发现上述异构体在不同温度下均很稳定,并且对弱酸、弱碱稳定.然而,随着溶液酸性的增强,杂卓4向杂卓5快速转化,而在强碱中两种异构体均发生分解.用TG/DSC技术、Kissinger法和Ozawa-Doyle法考察了上述异构体的热稳定性以及第一步分解过程的非等温动力学,确定了分解反应动力学参数(活化能E和指前因子A)及DTG峰温处的热力学参数(△G≠,△H≠,△S≠).s：The tautomerism of 3-ethoxycarbonyl-2,3/2,5-dihydro-1,5-benzothiazepines （imine tautomers 4/enamine tautomers 5） in various polar solvents（CD3OD,C6D6 ,CDCl3 ,DMSO-d6 ） was investigated using 1H NMR.The results showed that imines 4 and enamines 5 were stable in dry and aprotic solvents（C6D6 ,CDCl 3 and DMSO-d6 ）,but in protic solvent （CD 3 OD） the imine 4 undergo to their corresponding enamine tautomers.Base on good degree of differentiation in the UV spectroscopy of compounds 4 and 5 in DMSO or chloroform,the effects of temperature and pH of solutions on the imines 4 and enamines 5 tautomerism have been studied by UV spectral methods.It is found that imines 4 and enamines 5 were very stable at different temperature as well as under weak acidic or weak bases conditions.However,in strongly acidic solution of DMSO,the conversion of 4 to 5 was fast.While both of the tautomers decomposed in the presence of strong bases.The thermal properties of 4 and 5 were investigated by simultaneous TG-/DSC techniques.The kinetic parameters of the first decomposition stage for the title compounds were calculated by Kissinger’s method and Ozawa-Doyle’s method.The thermodynamic parameters （△H ≠ ,△G ≠ and△S ≠ ） at the peak temperatures of the DTG curves were also calculated.

关 键 词：1 5-苯并硫氮杂卓 亚胺 烯胺 互变异构 紫外光谱法 核磁共振法 非等温动力学 

分 类 号：TQ460.1[化学工程—制药化工]