Controlling Factors Determining the Selective HSCN Addition to Double Bonds and Their Application to the Synthesis of 7-Isothiocyano-7,8- -Dihydro-Bisabolene
نویسندگان
چکیده
A reatividade de duplas ligações terminal e trissubstituída de monoterpenos com HSCN foi examinada por CG evidenciando que fatores cinéticos são responsáveis pela adição quimiosseletiva em duplas ligações terminais em terpenos. O resultado mostra que a adição é cerca de 17 vezes mais rápida em duplas terminais do que em duplas trissubstituídas e que a presença do primeiro grupo SCN impede a entrada de um segundo grupo. A presença de um grupo hidroxila ou metoxila na molécula diminui sensivelmente a velocidade da reação. A partir do estudo acima foi possível elaborar e realizar a síntese do produto natural 7-isothiocyano-7,8-dihydro-bisabolene em duas etapas a partir do bisabolol.
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