40473-49-2Relevant articles and documents
A base-promoted cascade reaction of α,β-unsaturated: N -tosylhydrazones with o -hydroxybenzyl alcohols: Highly regioselective synthesis of N-sec -alkylpyrazoles
Chen, Lian-Mei,Zhao, Juan,Xia, An-Jie,Guo, Xiao-Qiang,Gan, Ya,Zhou, Chuang,Yang, Zai-Jun,Yang, Jun,Kang, Tai-Ran
supporting information, p. 8561 - 8570 (2019/10/02)
An efficient method for the synthesis of N-sec-alkylpyrazoles through a base-promoted cascade cyclization/Michael addition reaction of α,β-unsaturated N-tosylhydrazones with ortho-hydroxybenzyl alcohols has been developed. The desired products containing di- or triaryl groups at the same carbon atom were afforded in good to excellent yields with excellent regioselectivities (>20:1). Moreover, a three-component reaction of ortho-hydroxybenzyl alcohols, α,β-unsaturated N-tosylhydrazones and saturated N-tosylhydrazones also took place to afford pyrazoles in good yields. This reaction offers a new route to triarylmethanes with a simple operation and is applicable for large-scale synthesis.
Highly efficient preparation of optically active 5-hydroxy-3-oxoesters by enantioselective reaction of diketene with aldehydes promoted by novel chiral Schiff base-titanium alkoxide complexes
Hayashi,Tanaka,Oguni
, p. 1833 - 1836 (2007/10/03)
Optically active 5-hydroxy-3-oxoesters 1 can be obtained in up to 91% enantiomeric excess (e.e.) by the enantioselective reaction of diketene with aldehydes promoted by novel chiral Schiff base-titanium alkoxide complexes.
