主权项 |
1. A process for the synthesis of a compound of formula (I): wherein allyl cyanide of formula (II): is reacted, in the presence of a free radical initiator, with a compound of formula (III): wherein Xa represents a group —S—C(S)—OR in which R represents a linear or branched (C1-C6)alkyl group, to yield the compound of formula (IV): wherein Xa is as defined hereinbefore, wherein this latter compound may be optionally isolated, before being subjected to a cyclisation reaction in the presence of a free radical initiator in order to form the compound of formula (V): which compound of formula (V) may also be optionally isolated, which compound of formula (V) is subjected to a reduction-dehydration reaction to yield the compound of formula (VI): which is then subjected to an aromatisation reaction to yield the compound of formula (VII): which is subjected to reduction using hydrogen in the presence of Raney nickel in a polar protic medium and to reaction with acetic anhydride to yield the compound of formula (I), which is isolated in the form of a solid. |