Catalytic aldol-transfer reactions with Al-alkoxide trapping
摘要:
Al-BINOL catalyzed aldol-transfer reactions of aldehydes with diacetonealcohol conducted with Al-alkoxide trapping gave aldol adducts in good yields. The best yields were obtained with electron-rich aromatic aldehydes (e.g., 83% yield with 3,4,5-trimethoxybenzaldehyde). (c) 2006 Elsevier Ltd. All rights reserved.
Layered Double Hydroxides-Supported Diisopropylamide: Synthesis, Characterization and Application in Organic Reactions
作者:M. Lakshmi Kantam、A. Ravindra、Ch. Venkat Reddy、B. Sreedhar、B. M. Choudary
DOI:10.1002/adsc.200505266
日期:2006.3
The layereddoublehydroxides-supporteddiisopropylamide (LDH-DA) catalyst is found to be an efficient and selective solid base for aldol, Knoevenagel, Henry, Michael, transesterification and epoxidation reactions under liquid phase conditions. LDH-DA is synthesized by the interaction of lithium diisopropylamide with LDH-NO3 (as-synthesized) and calcined LDH-NO3. The LDH-DA (Mg/Al, 3/1) and their precursors
发现层状双氢氧化物负载的二异丙基酰胺(LDH-DA)催化剂是在液相条件下用于醇醛,Knoevenagel,Henry,Michael,酯交换和环氧化反应的有效且选择性的固体碱。LDH-DA是通过二异丙基氨基锂与LDH-NO 3(合成后)和煅烧的LDH-NO 3相互作用而合成的。通过使用各种仪器技术,如FT-IR,TGA和DTA,粉末XRD,固态27 Al MAS NMR光谱,SEM和XPS(ESCA ),可以很好地表征LDH-DA(Mg / Al,3/1)及其前体)。
Electron deficiency of aldehydes controls the pyrrolidine catalyzed direct cross-aldol reaction of aromatic/heterocyclic aldehydes and ketones in water
作者:Swapandeep Singh Chimni、Dinesh Mahajan
DOI:10.1016/j.tet.2005.03.045
日期:2005.5
A synthetically useful pyrrolidine catalyzed direct cross-aldol reaction of aromatic/heterocyclic aldehydes with ketones in water affords the aldol addition product in up to 93% yield. Electrophilicity of the aldehydes controls the course of the reaction.
Asymmetric organocatalysis with glycosyl-β-amino acids: direct asymmetric aldol reaction of acetone with aldehydes
作者:Namrata Dwivedi、Surendra S. Bisht、Rama P. Tripathi
DOI:10.1016/j.carres.2006.08.007
日期:2006.11
Directasymmetricaldolreaction of acetone with aromatic aldehydes was achieved in good yields and high enantioselectivity using 5-amino-5-deoxy-beta-L-ido-(alpha-D-gluco)-heptofuranuronic acids as a new class of organocatalysts.
Aldol reaction of 4-nitrobenzaldehyde with acetone gives 4-(4-nitrophenyl)-4-hydroxy-2-butanone in high yield in the presence of both secondary amine and mesoporous silica, whereas the yield is low in the absence of the mesoporous silica.
A novel Mg-Al-O-t-Bu hydrotalcite prepared for the first time, catalyses condensation reactions selectively to aldols (3) at 0 degrees C in quantitative yields. (C) 1998 Elsevier Science Ltd. All rights reserved.