ChemInform Abstract: 4‐Methyl‐3(10),4‐caradiene in the Diels‐Alder Reaction.

Skeletal rearrangements of monoterpenoids of the carane series

“…Such an effect was observed in the reaction of toluene-p-sulfonate 25 with lithium aluminium hydride 33 or triethylaluminium, 34 as well as upon its solvolysis. 35 Obviously, in an ideal case, this reaction should occur according to the S N 1 mechanism. However, it is likely that the reaction involves contact ion pairs: very strong polarisation of the substrate occurs, with an almost complete charge separation; however, the resulting cation is stabilised by the counter-ion.…”

“…However, pyrolysis of the alcohol 36 and its derivatives results not in the formation of a double bond but rather in cleavage of one of the bonds in the gemdimethylcyclopropane ring with simultaneous closure of a new three-membered carbocycle. Additional studies were carried out in order to study the mechanism of this unusual rearrangement: the kinetics of the thermal decomposition of the toluene-psulfonate 25 in pyridine 37 and its solvolysis 35 were studied.…”