Pinacol Coupling Reaction of β-Halo-α,β-unsaturated Aldehydes Promoted by TiI4
摘要:
[GRAPHICS]The pinacol reaction of beta-halogenated alpha,beta-unsaturated aldehydes was promoted by titanium tetraiodide to give coupling products in good yields with high di-selectivity. Subsequent reduction with H-2/Pd-C gave saturated vic-diols in good yields. Heck coupling reaction enabled the displacement of halogens with vinyl groups without the loss of stereochemical integrities.
First Pinacol Coupling in Emulsified Water: Key Role of Surfactant and Impact of Alternative Activation Technologies
作者:Muriel Billamboz、Christophe Len
DOI:10.1002/cssc.201500108
日期:2015.5.22
For the first time, the influence of surfactants on the radical pinacolcoupling reaction is investigated. The rate and selectivity of this reductive C‐C coupling are compared under three different activationtechnologies: thermal activation, microwave irradiation, and sonication. The use of IgepalCO520, a neutral surfactant, led to the successful conversion of aromatic or α,β‐unsaturated aliphatic
Selective Pinacol-Coupling Reaction using a Continuous Flow System
作者:Nicolas Sotto、Clément Cazorla、Carole Villette、Muriel Billamboz、Christophe Len
DOI:10.1021/acs.joc.6b02069
日期:2016.11.18
The first continuous flow pinacol coupling reaction of carbonyl compounds was successfully achieved within only 2 min during a single pass through a cartridge filled with zinc(0). The optimized method allowed the efficient production of gram-scale value-added compounds with high productivity. The developed methodology is efficient for aromatic or α,β-unsaturated aldehydes but gives moderate results
Selective Pinacol Coupling on Regeneratable Supported Acids in Sole Water
作者:Nicolas Sotto、Muriel Billamboz、Carole Chevrin-Villette、Christophe Len
DOI:10.1021/acs.joc.5b00837
日期:2015.6.19
Efficient pinacol coupling was developed in sole water, using a reusable heterogeneous supported acid source and zinc as cheap available metal source. This medium can be easily regenerated up to 10-fold without loss of activity. Moreover, supported acids enhance the selectivity of the pinacol coupling reaction compared with homogeneous acids.