Bicyclo(3.1.0)hexan-2-one, 5-(1-methylethyl)- → 3-Isopropyl-2-cyclopenten-1-one

Beteiligte Stoffe

Reaktionsschritte

In the process, however, a relatively greater number of steps have to be pursued up to the course of synthesis of sabina ketone (6). In addition, since sabine ketone is obtainable from the starting material 3-isopropyl-2-cyclopenten-1-one only in about 57% yield, the total yield of sabinene hydrate results in lower value. Moreover, according to the process, operations and works are complicated and laborious, as it requires isolation procedures for each intermediate. Further, it is necessary to use valuable reagents and chromate compound hazardous in handling. Therefore, sabinene hydrates cannot be produced efficiently or economically, in particular, in large scale. Furthermore, by the process, cis-sabinene hydrate (formula 8) is produced preferentially and trans-sabinene hydrate (formula 7) appears only in a considerably minor amount. That is to say, a ratio of formation of trans-compound to cis-compound is 1:8.5, so that the process does not suit an industrial synthesis of trans-sabinene hydrate. Also, yield of trans- and cis-sabinene hydrates from sabina ketone is about 11%, and yield from 3-isopropyl-2-cyclopenten-1-one is about 6.3%.

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