Pyrimidine-Derived Prolinamides as Recoverable Bifunctional Organocatalysts for Enantioselective Inter- and Intramolecular Aldol Reactions under Solvent-Free Conditions
作者:Pascuala Vizcaíno-Milla、José M. Sansano、Carmen Nájera、Béla Fiser、Enrique Gómez-Bengoa
DOI:10.1002/ejoc.201500007
日期:2015.4
ChiralL-prolinamides 2 containing the (R,R)- and (S,S)-trans-cyclohexane-1,2-diamine scaffold and a 2-pyrimidinyl unit are synthesized and used as general organocatalysts for intermolecular and intramolecular aldolreactions with 1,6-hexanedioic acid as a co-catalyst under solvent-free conditions. The intermolecular reaction between ketone–aldehyde and aldehyde–aldehyde must be performed under wet
Different bio/Lewis acid-catalyzed stereoselective aldol reactions in various mediums
作者:Tülay Yıldız、Hasniye Yaşa、Belma Hasdemir、Ayşe S. Yusufoğlu
DOI:10.1007/s00706-017-1967-z
日期:2017.8
Brønsted acids were used for asymmetric aldol reactions of aromatic, heteroaromatic, cyclic, and acyclic six ketones and eleven aldehydes. Optimum reaction conditions were determined by changing temperature and enzyme, ketone, aldehyde, solvent, cofactors types, amounts, and ratios. PPL (porcine pancreatic lipase) of animal and AL-AN (amano lipase A from Aspergillus niger) of fungal origins were the
A chemo-enzymatic oxidation/aldol sequential process directly converts arylbenzyl alcohols and cyclohexanol into chiral β-hydroxy carbonyls
作者:Yu Wang、Chengyi Wang、Qipeng Cheng、Yu Su、Hongyu Li、Rui Xiao、Chunxia Tan、Guohua Liu
DOI:10.1039/d1gc02831f
日期:——
transformation, an initial laccase-mediated oxidation of arylbenzyl alcohols and cyclohexanol to form aldehydes and cyclohexanone, followed by a subsequent proline derivative-catalyzed aldol condensation of the in situ generated intermediates, provides various 1,2-diastereoisomeric chiral β-hydroxy ketones with acceptable yields and high enantio-/diastereoselectivities.
Diastereo- and Enantioselective Direct Aldol Reactions in Aqueous Medium: A New Highly Efficient Proline-Sugar Chimeric Catalyst
作者:Silvana Pedatella、Mauro De Nisco、Domenico Mastroianni、Daniele Naviglio、Ada Nucci、Romualdo Caputo
DOI:10.1002/adsc.201100143
日期:2011.6
A new synthetic catalyst, capable of acting like an enzyme in the accomplishment of directaldolreactions, is presented. Excellent results, in terms of chemical yields and diastereo‐/enantiomeric ratios, are reported for the catalyzed additions of cyclohexanone to variously substituted benzaldehydes.
Facile one-pot fabrication of magnetic nanoparticles (MNPs)-supported organocatalysts using phosphonate as an anchor point through direct co-precipitation method
Novel MNP-supported organocatalysts were prepared by one-pot co-precipitation and surface modification using phosphonate as an anchor point, and exhibited excellent performance in aqueous asymmetric aldol reactions.