957770-94-4Relevant articles and documents
Application of a Heterogeneous Chiral Titanium Catalyst Derived from Silica-Supported 3-Aryl H8-BINOL to Enantioselective Alkylation and Arylation of Aldehydes
Akai, Junichiro,Watanabe, Satoshi,Michikawa, Kumiko,Harada, Toshiro
supporting information, p. 3632 - 3635 (2017/07/15)
A 3-aryl H8-BINOL was grafted on the surface of silica gel using a hydrosilane derivative as a precursor, and the resulting silica-supported ligand (6 mol %) was employed in the enantioselective alkylation and arylation of aldehydes in the pres
Catalytic enantioselective synthesis of diarylmethanols from Aryl bromides and aldehydes by using organolithium reagents
Nakagawa, Yuya,Muramatsu, Yusuke,Harada, Toshiro
experimental part, p. 6535 - 6538 (2011/02/22)
A general method has been developed for preparing enantioenriched secondary alcohols by starting from aryl bromides and aldehydes. Aryl bromides were first treated with BuLi, and the resulting aryllithium reagents were mixed with titanium tetraisopropoxide and magnesium bromide. The reaction of aldehydes with the resulting mixed titanium reagents, in the presence of 3-(3,5- diphenylphenyl)-H8-BINOL (2 mol-%) and titanium tetraisopropoxide, furnished the corresponding alcohols in high enantioselectivities and in high yields. Copyright
On the scope of trimethylaluminium-promoted 1,2-additions of ArZnX reagents to aldehydes
Glynn, Daniel,Shannon, Jonathan,Woodward, Simon
supporting information; experimental part, p. 1053 - 1060 (2010/05/19)
A practical asymmetric 1, 2 addition of functionalised arylzinc hal ides to aromatic and aliphatic aldehydes is described by the use of amino alcohol catalysis in the presence of AlMe3. The process is simple to carry out, uses only commercially available reagents/ligands and provides moderate to good (80-96% ee) enantioselectivities for a wide range of substrates. Either commercial ArZnX reagents or those prepared in situ from low cost aryl bromides can be used. In the latter case electrophilic functional groups are tolerated (CO2Et, CN). The reaction relies on rapid exchange between ArZnX and AlMe3 to generate mixed organometallic species that lead to the formation of a key intermediate that is distinctly different from the classic "anti" transition states of Noyori. NMR monitoring and related experments have been used to probe the validity of the proposed selective transition state.
