Myrcene, hydrosilylation

Myrcene (64) undergoes hydrosilylation preferentially at the terminal vinyl moiety to give a homo-allylsilane (65), as shown in equation (47). ... 

The reactions of metal complexes of monoterpenes continue to be actively explored and many specific examples will be found in later sections. Of general interest are the dimerization of 7r-allyl-Pd complexes of a- and p-pinenes and of carvone that are effected by irradiation at 366 nmM and the thermal decompositions of (TC-allyl)nickel halide complexes of, e.g., isoprene (33), to form myrcene.95 Hydrosilylation of 1,3-dienes e.g. isoprene, myrcene, ocimene) was found to be a regiospecific 1,4-addition for Pd complexes but followed the alternative route for Rh compounds a good discussion is appended.96 A series of dimers of isoprene... 

The hydrosilylation of myrcene with HSiClj also affords a mixture of mono- and diadduct. Of the two possible monoadducts, the 1,2-adduct is favored ... 

The regioselectivity observed in the hydrosilylation of myrcene is the same as with isoprene , but is much higher with ocimene. The reaction of ocimene with HSi(OEt)3 affords 2,6-dimethyl-8-triethoxysilylocta-2,6-diene in 98% regioselectivity ... 

The hydrosilylation of myrcene or ocimene proceeds also regioselectively and stereo-selectively to give the corresponding 1,4-adduct in high yield (equations 39 and 40), with the exception of the reaction of ocimene with trichlorosilane in which 1,2-adduct is a major product91. 

Regioselectivity observed in the hydrosilylation of myrcene is largely the same as that of isoprene91. In contrast to this, the regioselectivity achieved in the hydrosilylation of ocimene by the rhodium(I) catalyst is much higher than that attained in the reactions of isoprene and myrcene. Especially, the reaction of ocimene with triethoxysilane affords 2,6-dimethyl-8-triethoxysilyl-2,6-octadiene in 98% regioselectivity91 (equation 49). 

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