Exocyclic Alkylidene Carbenes - An ab initio Theoretical Study.

✍ Scribed by Yitzhak Apeloig; Ruth Schrieber; Peter J. Stang

• Book ID: 104237215
• Publisher: Elsevier Science
• Year: 1980
• Tongue: French
• Weight: 237 KB
• Volume: 21
• Category: Article
• ISSN: 0040-4039
• DOI: 10.1016/s0040-4039(01)85487-3

✦ Synopsis

ab initio calculations were carried out for three exocyclic allcylidene carbenes. Cyclopentadienylvinyl carbene is predicted to be highly electrophilic while the cyclopropenylidenevinyl carbene may provide the first example of a nucleophilic alkylidene carbene.

Unsaturated carbenes 1, where the divalent carbon (carbenic center) is an integral part of an unsaturated system have recently attracted the attention of both experimentalists' and theoreticans.

2 New synthetic methods now provide easy access to this novel and useful class of reaction intermediates.

1 Of special interest synthetically as well as mechanistically are exocyclic alkylidene carbenes such aa 2, 2 and i. Carbene 2 for example, could provide an enetry to the unknown 2. In conjugation with experimental efforts to generate 2 -4 we have also investigated these species computationally in order to provide basic information on their stabilities and to gain insight into their properties. The results are reported in this communication.