53207-58-2Relevant articles and documents
Conversion of Aldehydes to Branched or Linear Ketones via Regiodivergent Rhodium-Catalyzed Vinyl Bromide Reductive Coupling-Redox Isomerization Mediated by Formate
Swyka, Robert A.,Shuler, William G.,Spinello, Brian J.,Zhang, Wandi,Lan, Chunling,Krische, Michael J.
supporting information, p. 6864 - 6868 (2019/05/10)
A regiodivergent catalytic method for direct conversion of aldehydes to branched or linear alkyl ketones is described. Rhodium complexes modified by PtBu2Me catalyze formate-mediated aldehyde-vinyl bromide reductive coupling-redox isomerization to form branched ketones. Use of the less strongly coordinating ligand, PPh3, promotes vinyl-to allylrhodium isomerization en route to linear ketones. This method bypasses the 3-step sequence often used to convert aldehydes to ketones involving the addition of pre-metalated reagents to Weinreb or morpholine amides.
A PROCESS FOR THE PREPARATION OF FIROCOXIB
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Page/Page column 20; 21, (2018/07/05)
The present invention provides an improved process for preparation of Firocoxib of Formula I. Further, the present invention relates to novel process for the preparation of crystalline polymorphic form B of Firocoxib of Formula I.
NEW PROCESS FOR THE SYNTHESIS OF FIROCOXIB
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Page/Page column 4; 7; 12; 13; 17, (2018/11/10)
The present invention concerns a process for the preparation of firocoxib, i.e. 3-(cyclopropylmethoxy)-5,5-dimethyl-4-(4-methylsulfonylphenyl)-furan-2-one, comprising steps (a)-(g), wherein the process provides for step (d) of the reaction of a new intermediate, i.e. 2-methyl-1-[4-(methylsulfanyl)phenyl]-1-oxopropan-2-yl (acetyloxy)acetate (compound VII) in the same organic solvent of step (a) in the presence of a catalyst and a phase transfer catalyst solution in the same organic solvent with hydrogen peroxide.