138567-02-9Relevant articles and documents
New evidence on the regiochemistry of the tert-butyldiphenylsilylcupration of allene using the silylcuprate or silylcopper reagent
Cuadrado, Purificación,González-Nogal, Ana M.,Sánchez, Alicia,Sarmentero, M. Angeles
, p. 5855 - 5859 (2003)
The regiochemistry in the tert-butyldiphenylsilylcupration of the allene depends on the temperature and also on the nature of the electrophile. Thus, the intermediate generated by addition of the silylcuprate at -78°C reacted with electrophiles to give allylsilanes, except with oxo compounds which afforded vinylsilanes. On the other hand, the silylcopper reagent was added at -40°C leading, in all cases, to the corresponding allylsilanes. When enones were used as electrophile the vinylsilanes were the 1,2-addition products and the allylsilanes those from 1,4-addition. These functionalized vinyl or allyl tert-butyldiphenylsilanes are interesting synthons for the preparation of conjugated tert-butyldiphenylsilyltrienes and functionalized exocyclic alkylidenecyclopentenes.
The Reaction of tert-Butyldiphenylsilylcuprates with Allenes
Barbero, Asuncion,Cuadrado, Purificacion,Gonzalez, Ana M.,Pulido, Francisco J.,Fleming, Ian
, p. 2811 - 2816 (2007/10/02)
Bis(tert-butyldiphenylsilyl)cuprate 1 reacts with allenes to form allyl- and vinyl-silanes.With allene itself the cuprate reagent shows a different regiochemistry from that of bis(phenyldimethylsilyl)cuprate.The regiochemistry can be controlled by choosing an appropriate reaction temperature.The intermediate cuprate 4 resulting from the addition of 1 to allene reacts with a wide variety of electrophiles giving functionalised allylsilanes.Phenylallenes isomerise to acetylenes.
