6214-44-4Relevant articles and documents
Reduction over Condensation of Carbonyl Compounds through a Transient Hemiaminal Intermediate Using Hydrazine
Vilches-Herrera, Marcelo,Gallardo-Fuentes, Sebastián,Aravena-Opitz, Mauricio,Yá?ez-Sánchez, Mauricio,Jiao, Haijun,Holz, Jens,B?rner, Armin,Lühr, Susan
, p. 9213 - 9218 (2020/08/14)
Reduction of carbonyl moieties to the corresponding alcohol using simply hydrazine hydrate has been considerably unfeasible until now due to the well-known condensation reaction. However, herein, we report that using an excess of 20-fold equivalents, the reduction proceeds in excellent yields. 1H NMR study of the reaction and density functional theory (DFT) calculations indicate that the final fate of the hemiaminal intermediate is crucial to obtain the alcohol or the hydrazone.
Preparation method of sugar-reducing medicine dapagliflozin
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Paragraph 0050; 0054-0056, (2019/10/01)
The invention discloses a preparation method for hypoglycemic drugdapagliflozin. The method comprises the steps that 4-hydroxybenzaldehyde is adopted as a starting raw material, alkylation, carbonyl reduction, chlorination and alkylation reaction with asepsin, diazotization and chlorination are performed to obtain a dapagliflozinmidbody 5-bromo-2-chloro-4'-ethyoxyl diphenylmethane, then, the midbody and 2,3,4,6-tetra-O-trimethyl silicone-D-glucolactone are subjected to condensation, etherification and methoxyl removal to obtain the hypoglycemic drugdapagliflozin. The raw materials adopted by the technological path are low in price and easy to obtain, the technology can achieve industrialization easily, and the final product is high in purity; the technological path is novel, the syntheticroute is short, no risky or complex technology exists in the reactions, equipment is simple, operation is easy and convenient, and the method is suitable for industrial production.
Selective Hydroboration of Carboxylic Acids with a Homogeneous Manganese Catalyst
Barman, Milan K.,Das, Kuhali,Maji, Biplab
, p. 1570 - 1579 (2019/01/30)
Catalytic reduction of carboxylic acid to the corresponding alcohol is a challenging task of great importance for the production of a variety of value-added chemicals. Herein, a manganese-catalyzed chemoselective hydroboration of carboxylic acids has been developed with a high turnover number (>99?000) and turnover frequency (>2000 h-1) at 25 °C. This method displayed tolerance of electronically and sterically differentiated substrates with high chemoselectivity. Importantly, aliphatic long-chain fatty acids, including biomass-derived compounds, can efficiently be reduced. Mechanistic studies revealed that the reaction occurs through the formation of active manganese-hydride species via an insertion and bond metathesis type mechanism.
