A diversity-oriented synthesis of polyheterocycles <i>via</i> the cyclocondensation of azomethine imine
作者:Arshad J. Ansari、Ramdas S. Pathare、Anita Kumawat、Antim K. Maurya、Sarika Verma、Vijai K. Agnihotri、Rahul Joshi、Ramesh K. Metre、Ashoke Sharon、R. T. Pardasani、Devesh M. Sawant
DOI:10.1039/c9nj02874a
日期:——
reactions to afford skeletally diverse molecules are described. The reaction involved azomethineimine formation and a cyclocondensation reaction as individual steps. The methodology provides excellent regio- and stereocontrol. Skeletal diversity was ensured by changing the electrophilic counterpart of azomethineimine. Due to its broader diversity and complexity, the DOS methodology is likely to benefit
An efficient [3+2] cycloaddition for the synthesis of substituted pyrazolo[1,5-c]quinazolines
作者:Tao Wang、Ailong Shao、Haiyan Feng、Shuwu Yang、Meng Gao、Jun Tian、Aiwen Lei
DOI:10.1016/j.tet.2015.03.019
日期:2015.7
and efficient [3+2] cycloaddition reaction between N-iminoquinazolinium ylide and nitroolefins was developed. From a synthetic point of view, this protocol represents an efficient way to pyrazolo[1,5-c]quinazolines derivatives.
开发了N-亚氨基喹唑啉鎓叶立德和硝基烯烃之间简单有效的[3 + 2]环加成反应。从综合的观点来看,该方案代表了吡唑并[1,5- c ]喹唑啉衍生物的有效方法。
Squaramide-catalysed enantio- and diastereoselective sulfa-Michael addition of thioacetic acid to α,β-disubstituted nitroalkenes
作者:Wen Yang、Da-Ming Du
DOI:10.1039/c2ob26068a
日期:——
A highly enantio- and diastereoselective sulfa-Michael addition of thioacetic acid to α,β-disubstituted nitroalkenes catalysed by a chiral squaramide organocatalyst has been described. This organocatalytic reaction at an extremely low catalyst loading (0.2 mol%) furnished synthetically useful β-nitro sulfides in excellent yields with good diastereoselectivities and high enantioselectivities (up to 94â:â6 dr, 95% ee). In addition, the catalytic reaction can be performed on a 10 gram scale, and facile transformation into taurine derivative is also presented.
Asymmetric <i>C</i>-Alkylation of Nitroalkanes <i>via</i> Enzymatic Photoredox Catalysis
作者:Haigen Fu、Tianzhang Qiao、Jose M. Carceller、Samantha N. MacMillan、Todd K. Hyster
DOI:10.1021/jacs.2c12197
日期:2023.1.18
Tertiary nitroalkanes and the corresponding α-tertiary amines represent important motifs in bioactive molecules and natural products. The C-alkylation of secondary nitroalkanes with electrophiles is a straightforward strategy for constructing tertiary nitroalkanes; however, controlling the stereoselectivity of this type of reaction remains challenging. Here, we report a highly chemo- and stereoselective