Vasicine from Adhatoda vasica as an organocatalyst for metal-free Henry reaction and reductive heterocyclization of o-nitroacylbenzenes
作者:Sushila Sharma、Manoranjan Kumar、Vinod Bhatt、Onkar S. Nayal、Maheshwar S. Thakur、Neeraj Kumar、Bikram Singh、Upendra Sharma
DOI:10.1016/j.tetlet.2016.09.095
日期:2016.11
Vasicine, a quinazolinealkaloid, from the leaves of Adhatodavasica, has been utilized as an efficient catalyst for metal and base free Henry reaction of various aldehydes with nitro alkanes. The method can be used in the synthesis of various β-nitro alcohols under mild reaction conditions without use of hazardous organic solvents and expensive catalysts. Vasicine is also applied successfully for
Biphenyl-Based Bis(thiourea) Organocatalyst for Asymmetric and syn-Selective Henry Reaction
作者:Pavel Bobal、Jan Otevrel
DOI:10.1055/s-0036-1588594
日期:——
excellent enantioselectivities. The achieved high reactivity and enantioselectivity in the nitroaldol reaction of nitroalkanes with aromatic aldehydes suggests promising potential for this catalyst. Moreover, a significant syn-diastereoselectivity was observed. A scalable, efficient and chromatography-free synthesis of a new enantiopure C 2-symmetric bis(thiourea) catalyst was accomplished from a readily
Cascade Formation of Isoxazoles: Facile Base-Mediated Rearrangement of Substituted Oxetanes
作者:Johannes A. Burkhard、Boris H. Tchitchanov、Erick M. Carreira
DOI:10.1002/anie.201100260
日期:2011.5.27
Give me five! Nitro compounds and oxetan‐3‐one react through an intriguing cascade sequence to give isoxazole‐4‐carbaldehydes using inexpensive reagents in a one‐pot procedure (see scheme; Ms=methanesulfonyl). A variety of 3‐substitutedisoxazole‐4‐carbaldehydes were obtained in high overall yields.
击个掌!硝基化合物和oxetan-3-one通过一个有趣的级联序列反应,使用便宜的试剂在单锅法中制得异恶唑4-甲醛(见方案; Ms =甲磺酰基)。以高总收率获得了各种3-取代的异恶唑-4-甲醛。
Henry Reaction in Aqueous Media at Neutral pH
作者:Pranjal P. Bora、Ghanashyam Bez
DOI:10.1002/ejoc.201201682
日期:2013.5
An efficient method for the synthesis of β-nitro alcohols from nitro alkanes and aldehydes in aqueous phosphate buffer under neutral pH conditions at room temperature is reported. In the case of higher nitro alkanes, the reaction showed very good diastereoselectivity to give syn β-nitro alcohols in preference to their anti products.
Optically active nitro alcohol derivatives, optically active amino alcohol derivatives, and process for producing thereof
申请人:——
公开号:US20020193447A1
公开(公告)日:2002-12-19
Optically active 1-substituted phenyl-2-nitro alcohol derivatives having the formula (1)
1
and the process for producing thereof, and 1-substituted phenyl-2-amino alcohol derivatives having the formula (2)
2
and the process for producing thereof from the optically active 1-substituted phenyl-2-nitro alcohol derivatives. From these nitro alcohols, pharmaceuticals such as (R)-albutamin and (R)-sarmeterol useful as a bronchodilator is obtained via optically active amino alcohols which are useful pharmaceutical intermediates.