The reactions of trans-2,3-dimethylcyclopropyl methylene produced photolytically in the gas phase

✍ Scribed by Angelo Guarino; Alfred P. Wolf

• Publisher: Elsevier Science
• Year: 1969
• Tongue: French
• Weight: 188 KB
• Volume: 10
• Category: Article
• ISSN: 0040-4039
• DOI: 10.1016/s0040-4039(01)87774-1

✦ Synopsis

A previous communication (1) has reported the synthesis and photolysis of cyclopropyldiazomethane.

The intention of that work was to study the decomposition of the intermediate carbene (analogous to the presumed carbene produced in the reaction of hot carbon atoms with cyclopropane (2,3) and the presumed carbene produced in the carbon atom reactions described by Engel and Skell (4)) and attempt to correlate product distribution with mechanism and method of carbene production.

Major products of decomposition are acetylene and ethylene, which arise from homolytic bond scission of the ring in the carbene. It is clear that more light could be shed on this whole process if the cyclopropane ring were substituted in such a way as to allow a "nascent" substituted ethylene a stereochemical choice in going to product.

To this end, trans-2,3-dimethylcyclopropyldiazomethane was prepared in a six step synthesis starting with trans-2,3_dimethylcyclopropyl chloride obtained from a ring forming reaction with butyl lithium and methylene chloride using the method of Closs and ClOSS (5). The chloride was converted to the carboxylic acid: the acid converted to the acid chloride: the acid chloride converted to the amide: and the amide reduced to the amine.

The amine was diaaotized to the diazo compound by the method of Adamson and Kenner (6). The purification of the diazo compound (exclusively the trans-dimethyl compound at this point), a beautiful orange yellow colored liquid, was accomplished by a bulb to bulb distillation in a high vacuum system by conventional high vacuum * Research performed under the auspices of the U. S. Atomic Energy Commission.