Addition of hydrazine to natural terpene-based isothiocyanates derivatives: density functional theory investigation

作者：Patrick da Silva Alan; de Freitas Gauze Gisele; Pereira Coelho Narcimario; Conceicao da Silva Cleuza; Abicht Basso Ernani

来源：Tetrahedron Letters, 2011, 52(1): 62-64.

DOI：10.1016/j.tetlet.2010.10.145

• Thiosemicarbazides
• Isothiocyanates
• Transition states
• Theoretical calculations

The hydrazine addition to isothiocyanoterpenes to produce thiosemicarbazides occurs with excellent yields. The reaction rate to conversion of the camphene-based (NCS1), R-(+)-limonene-based (NCS2), and (-)-alpha-bisabolol-based (NCS3) isothiocyanoterpene derivatives in the respective thiosemicarbazides was experimentally studied. It was observed that NCS3 reacts two times faster than NCS2 and 3.5 times faster than NCS1. A complete theoretical investigation of the transition states of these reactions was accomplished, showing that the difference in the reaction rates can be explained by the differences in the electrophilic character of the -NCS group and the relative stability of the proposed transition states.

• 出版日期2011-1-5