根据反应条件,在3-NH位置或5-氨基选择性地进行5-氨基-3 H -1,3,4-噻二唑啉-2-酮(2)的酰化。3-NH是高酸性的,在吡啶或三乙胺的存在下,在该位置用酸酐以高收率进行酰化反应。只有通过5-氨基-3-酰基-1,3,4-噻二唑啉-2-酮中间体4才能使3-位和5-氨基的二酰基化。在中性条件下,酰化仅在5-氨基上与酰基氯形成5-酰基氨基-3 H -1,3,4-噻二唑啉-2-酮5发生。5-乙酰氨基-3 H-1,3,4-噻二唑啉-2-酮还可以通过在乙酸中热转化5-氨基-3-乙酰基-1,3,4-噻二唑啉-2-酮来合成。
根据反应条件,在3-NH位置或5-氨基选择性地进行5-氨基-3 H -1,3,4-噻二唑啉-2-酮(2)的酰化。3-NH是高酸性的,在吡啶或三乙胺的存在下,在该位置用酸酐以高收率进行酰化反应。只有通过5-氨基-3-酰基-1,3,4-噻二唑啉-2-酮中间体4才能使3-位和5-氨基的二酰基化。在中性条件下,酰化仅在5-氨基上与酰基氯形成5-酰基氨基-3 H -1,3,4-噻二唑啉-2-酮5发生。5-乙酰氨基-3 H-1,3,4-噻二唑啉-2-酮还可以通过在乙酸中热转化5-氨基-3-乙酰基-1,3,4-噻二唑啉-2-酮来合成。
MASS SPECTROMETRIC STUDIES OF 3-SUBSTITUTED-5-AMINO-1,3,4-THIADIAZOLIN-2-ONES
作者:Un Chul Lee、Won Lee、Yun Je Kim、Song Ja Park、Do Young Ra、Nam Sook Cho
DOI:10.1080/10426509808035690
日期:1998.8.1
Fragment pathways of 3-alkyl and acyl-5-amino-1,3,4-thiadiazolin-2-ones were completely assigned by mass analyzed kinetic energy spectra (MIKE), collisional activated dissociation (CAD) spectra and high resolution mass spectra. [NH2CS](+) and [S=C=O](+) ions were directly formed from molecular ion of the 3-alkyl compounds and from 5-amino-3H-1,3,4-thiadiazolin-2-one ion (1) which was produced by McLafferty rearrangement from molecular ion of 3-acyl compounds. A loss of neutral SCO was only detected from 3-alkyl substituted molecular ions.
Lee, Un Chul; Lee, Won; Kim, Yun Je, Phosphorus, Sulfur and Silicon and the Related Elements, 1997, vol. 126, p. 201 - 210
作者:Lee, Un Chul、Lee, Won、Kim, Yun Je、Park, Song Ja、Ra, Do Young、Cho, Nam Sook