89979-04-4Relevant articles and documents
Revisit to Henry reaction by non conventional heterogeneous and efficient catalyst for nitroalcohol synthesis
Jadhav, Swati D.,Patil, Rupesh C.,Jagdale, Ashutosh A.,Patil, Suresh S.
, p. 593 - 606 (2021/11/03)
A sustainable, green and efficient process for the synthesis of 2-nitro alcohol derivatives from different substituted aromatic aldehydes with nitroalkane by stirring at ambient temperature with high product yield is reported. Adoption of very mild reaction conditions, use of Calcined Eggshell (CES) as natural catalyst and simple workup are expected to contribute to the development of environmentally benign synthetic method for Henry (nitroaldol) reaction. CES is ecologically safe, inexpensive, and attractive heterogeneous base catalyst obtained from renewable resources, thus opening a new perspective for this process. Graphical abstract: [Figure not available: see fulltext.]
Metal-Free Deoxygenation of Chiral Nitroalkanes: An Easy Entry to α-Substituted Enantiomerically Enriched Nitriles
Pirola, Margherita,Faverio, Chiara,Orlandi, Manuel,Benaglia, Maurizio
supporting information, p. 10247 - 10250 (2021/06/18)
A metal-free, mild and chemodivergent transformation involving nitroalkanes has been developed. Under optimized reaction conditions, in the presence of trichlorosilane and a tertiary amine, aliphatic nitroalkanes were selectively converted into amines or nitriles. Furthermore, when chiral β-substituted nitro compounds were reacted, the stereochemical integrity of the stereocenter was maintained and α-functionalized nitriles were obtained with no loss of enantiomeric excess. The methodology was successfully applied to the synthesis of chiral β-cyano esters, α-aryl alkylnitriles, and TBS-protected cyanohydrins, including direct precursors of four active pharmaceutical ingredients (ibuprofen, tembamide, aegeline and denopamine).
One-Pot Enzyme Cascade Catalyzed Asymmetrization of Primary Alcohols: Synthesis of Enantiocomplementary Chiral β-Nitroalcohols
Chatterjee, Ayon,Kumar Padhi, Santosh,Rao, D. H. Sreenivasa
supporting information, p. 5310 - 5318 (2021/10/02)
Biocatalytic asymmetrization of inexpensive and stable primary alcohols to prepare enantioenriched β-nitroalcohols is an important development in green chemistry for the production of chiral pharmaceutical intermediates. Herein, we report a one-pot, two-step cascade reaction sequence in which first benzylic alcohols were oxidized to produce corresponding benzaldehydes using horse liver alcohol dehydrogenase (HLADH). The in situ generated aldehydes were then reacted in a biphasic medium with nitromethane by Arabidopsis thaliana hydroxynitrile lyase (AtHNL) or Baliospermum montanum HNL (BmHNL) catalyzed Henry reaction to produce stereoselective β-nitroalcohols with (R) or (S) configuration, respectively. Using HLADH-AtHNL, (R)-β-nitroalcohols were obtained in up to 64% conversion, and HLADH-BmHNL, (S)-β-nitroalcohols in up to 70% conversion, while in both cases excellent stereoselectivity (up to >99% ee) was achieved. The concept was proven by functionalization of sp3 C?H bond of ten simple achiral benzylic alcohols to enantiocomplementary chiral β-nitroalcohols. (Figure presented.).
