Key points are not available for this paper at this time.
An ideal supplement to Li−, Mg−, and Zn–ene reactions is provided by the cyclization of 2,7- and 2,8-dienes, -enynes, and -diynes having a leaving group at the C1 position with the TiII equivalent 1 (see below; R = R′ = alkyl, aryl). In this reaction, the alkenyltitanium intermediate is presumably formed via a bicyclic titanium compound and not via an open-chain alkenyltitanium compound.
Takayama et al. (Fri,) studied this question.