Enantioselective synthesis of fused heterocycles with contiguous stereogenic centers by chiral phosphoric acid catalyzed symmetry breaking
作者:Keiji Mori、Ayaka Miyake、Takahiko Akiyama
DOI:10.1039/c5cc05508c
日期:——
Highly enantioselective synthesis of fused-heterocycles was achieved by chiral phosphoric acid catalyzed symmetry breaking.
手性磷酸催化的对称破坏实现了高度对映选择性的融合杂环化合物的合成。
Towards organo-click reactions: development of pharmaceutical ingredients by using direct organocatalytic bio-mimetic reductions
作者:Dhevalapally B. Ramachary、G. Babul Reddy
DOI:10.1039/b612611a
日期:——
Economic and environmentally friendly bio-mimetic one-pot three and four-component Knoevenagel–hydrogenation (K–H), five-component Knoevenagel–hydrogenation–alkylation (K–H–A) and six-component Knoevenagel–hydrogenation–alkylation–Huisgen cycloaddition (K–H–A–HC) reactions of aldehydes, CH-acids, o-phenylenediamine, alkyl halides and azides using proline, proline–metal carbonate and proline–metal carbonate–CuI-catalysis, respectively have been developed. Many of K–H and K–H–A compounds have direct application in pharmaceutical chemistry.
Chiral effectiveness: The title transformation is applicable to a wide variety of substrates to give chiralcyclohexenones in high yields and with excellent enantioselectivity (see scheme). To clarify the origin of the enantioselectivity ONIOM calculations were carried out
Development of Pharmaceutical Drugs, Drug Intermediates and Ingredients by Using Direct Organo-Click Reactions
作者:Dhevalapally B. Ramachary、Mamillapalli Kishor、Y. Vijayendar Reddy
DOI:10.1002/ejoc.200701014
日期:2008.2
two-carbon homologation through cascade O/H/H reactions of aldehydes 1, Meldrum's acid (3c), Hantzsch ester (4) and acetic acid/triethylamine in ethanol has been demonstrated. Additionally, we have developed a green synthesis of the highly substituted 1,2,3-triazole 17 from simple substrates through a two-step combination of olefination/hydrogenation/alkylation and Huisgen cycloaddition reaction sequences
Ruthenium-catalysed C-alkylation of 1,3-dicarbonyl compounds with primary alcohols and synthesis of 3-keto-quinolines
作者:Elena Cini、Elena Petricci、Giuseppina I. Truglio、Marialaura Vecchio、Maurizio Taddei
DOI:10.1039/c6ra03585j
日期:——
mono-alkylation of 1,3-diketones using alcohols is possible in the presence of catalytic amounts of Ru(CO)(PPh3)3HCl and 10% mol of the Hantzsch ester. The borrowinghydrogenprocess between the catalyst and the dihydropyridine/pyridine couple prevents the common double alkylation of the Knoevenagel adduct without the need of stoichiometric reducing agents or sacrificial nucleophiles. The reaction was applied to