Generation of Reactive Low-Valent Titanium Species Using Μetal−Αrenes as Efficient Organic Reductants for TiCl<sub>3</sub>: Applications to Organic Synthesis
for TiCl(3) has resulted in an efficient method for the generation of highly reactive low-valent titanium (LVT) reagents. The activated titanium species could be prepared by refluxing a mixture of substoichiometric amounts of arenes, TiCl(3), and Li/Mg in THF or DME. Among the LVT reagents screened, TiCl(3)--Li--naphthalene--THF (reagent I) was the best for coupling of carbonyls to olefins. The reagent
Highly active salted low-valent titanium reagents for various SET induced reactions
作者:Shyam Rele、Subrata Chattopadhyay、Sandip K Nayak
DOI:10.1016/s0040-4039(01)02009-3
日期:2001.12
External addition of inorganic salts (Group I and II metal halides) to the preformed low-valenttitanium reagent A (TiCl3–Li–THF) dramatically enhanced its activity. The new reagents were used to carry out various SET reactions including McMurry's olefination at a faster rate even at ambient temperature.
Salt/ligand-activated low-valent titanium formulations: the ‘salt effect’ on diastereoselective carbon–carbon bond forming SET reactions
作者:Shyam M. Rele、Sandip K. Nayak、Subrata Chattopadhyay
DOI:10.1016/j.tet.2008.05.084
日期:2008.7
the construction of highly efficient low-valenttitanium (LVT) reagents. These salt-activated LVT reagents while exhibiting enhanced chemoselectivity and diastereoselectivity accelerated the reductive olefination rates of aromatic and aliphatic carbonyls under ambient temperature conditions and in much reduced reaction times. The versatility of the salted reagent was further explored in other single