Categories: C-Br Bond Formation >
Synthesis of 1,1-dibromoalkanes
Application of (PhO)3P-halogen-based reagents allows the preparation of vinyl halides in good to excellent yields from enolizable ketones, whereas aldehydes afforded the corresponding gem-dihalides. The halogenation proceeded smoothly under mild conditions.
A. Spaggiari, D. Vaccari, P. Davoli, G. Torre, F. Prati, J. Org. Chem., 2007, 72, 2216-2219.
The combination of Ph3P and easily available 1,2-dihaloethanes (XCH2CH2X; X = Cl, Br, or I), was very effective for a mild deoxygenative halogenation of alcohols and aldehydes. The use of (EtO)3P instead of Ph3P enables a convenient purification process, as the byproduct (EtO)3P═O could be removed by aqueous washing. A dehydroxy-fluorination proceeds well in the presence of ICH2CH2I and CsF as fluoride source in DMF.
J. Chen, J.-H. Lin, J.-C. Xiao, Org. Lett., 2018, 20, 3061-3064.