The reaction of 4-amino-2-oxazolines with isocyanates and isothiocyanates. Synthesis and X-ray structures of polysubstituted 2-imidazolidinones, 1,3-oxazolidines and 1,3-thiazolidines
作者:Antonio Guirado、Raquel Andreu、Bruno Martiz、Delia Bautista、Carmen Ramírez de Arellano、Peter G. Jones
DOI:10.1016/j.tet.2006.04.058
日期:2006.6
However, the reactions with non-sulfonylated isocyanates or isothiocyanates were slower, leading to the expected ureido and thioureido derivatives 5, which were easily and efficiently transformed to either polysubstituted 2-imino-1,3-oxazolidine or 2-imino-1,3-thiazolidine hydrochlorides 7, respectively, by treatment with hydrochloric acid. The possible reasons for this disparity in chemical behaviour are
4-烷基氨基-2-苯基-2-恶唑啉1与异氰酸酯和异硫氰酸酯的反应提供了空前有效的区域选择性杂环-杂环转化。化合物1与异氰酸甲苯酯快速反应,以几乎定量的产率直接产生3-烷基-4-苯甲酰胺基-1-甲苯磺酰基-2-咪唑啉酮4。相应的脲基中间体2不是可分离的物质。然而,与非磺酰化异氰酸酯或异硫氰酸酯的反应较慢,从而导致预期的脲基和硫脲基衍生物5,它们易于有效地转化为多取代的2-亚氨基-1,3-恶唑烷或2-亚氨基-1,3。 -噻唑烷盐酸盐7分别用盐酸处理。讨论了这种化学行为差异的可能原因。4-苯甲酰胺基-3-甲基-1-甲基-1-甲苯基-2-咪唑啉酮4b,4- [1-异丙基-3-(4-硝基苯基)脲基] -2-苯基-2-恶唑啉5e,(的X射线晶体结构已经确定了Z)-3-苄基-4-苯甲酰胺基-2-苯基亚氨基-1,3-恶唑烷盐酸盐7a和(Z)-3-苄基-4-苯甲酰胺基-2-苯基亚氨基-1,3-噻唑烷盐酸盐7b。