Phenothiazine → 3-Methoxycyclohepta-1,3,5-triene

Participants

Reaction Conditions

Reaction Steps

Phenothiazine (1.4 gm=0.1% by weight of 7-methoxycycloheptatriene) was dissolved in 1381.9 gm of distilled 7-methoxycycloheptatriene. The solution was then heated under nitroen at ambient pressure for 2 hours at 150° C., during which time low-boiling materials were removed by a condenser set for downward distillation. Upon cooling, the residual material weighed 1345.2 grams, representing a crude yield of 97.3% (based on initial 7-methoxy isomer). NMR analysis indicated a product composition of 76 mole % 3-methoxycyclohepta-1,3,5-triene, 12 mole % 1-methoxycyclohepta-1,3,5-triene and 4 mole % unconverted 7-methoxy isomer. The product was of sufficiently good quality to be utilized for conversion to 1-methoxycycloheptatriene without prior distillation.

Provenance & Evidence