نتایج جستجو برای: achiral

تعداد نتایج: 1375  

Journal: :Journal of Synthetic Organic Chemistry, Japan 1996

Journal: :Chemical communications 2013
Yun-Lin Liu Jian Zhou

We report the first catalytic asymmetric cyanation of N-Boc ketoimines, which enables highly enantioselective synthesis of oxindole based α-amino nitriles. An unprecedented tandem aza-Wittig/Strecker reaction is also developed, emerging as a promising strategy for the catalytic asymmetric cyanation of ketoimines formed in situ from achiral ketones.

Journal: :Nanoscale 2015
Bo Song Bin Liu Yingzhi Jin Xingxing He Danting Tang Guanglu Wu Shouchun Yin

Helical nano-ribbons with a large aspect ratio were obtained through the self-assembly of an achiral amphiphile. The symmetry breaking is attributed to the orderly but twisted stacking of terpyridine groups. In addition, the morphology of the assemblies can be tuned by the coordination between terpyridine and Zn(2+) ion.

Journal: :Angewandte Chemie 2012
Xi-Feng Tu Liu-Zhu Gong

A little gold goes a long way: as little as 0.01 mol % of chiral gold phosphate is sufficient to afford the asymmetric transfer hydrogenation of quinolines with high stereoselectivity (up to 98 % ee). The achiral ligands on gold were found to have considerable effect on the catalytic efficiency.

2014
Pankaj Chauhan Gregor Urbanietz Gerhard Raabe Dieter Enders

A highly stereoselective one-pot procedure involving an enantioselective Michael addition promoted by low loading of an amino-squaramide catalyst followed by an achiral base catalyzed domino Michael-Knoevenagel-type 1,2-addition sequence provides efficient access to fully substituted cyclohexanes bearing five contiguous stereogenic centers in good yields (68-86%) and excellent stereoselectiviti...

Journal: :Organic & biomolecular chemistry 2012
Valentina Cerulli Luca Banfi Andrea Basso Valeria Rocca Renata Riva

A highly diastereoselective Ugi reaction involving a chiral cyclic imine, two enantiomerically pure isocyanides and various carboxylic acids was employed for the synthesis of polyfunctionalized pyrrolidines. Both chiral substrates have been efficiently prepared by chemoenzymatic methodologies from readily available achiral substrates. This highly convergent approach can find an application in t...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید