We report a solid-acid catalyzed aminolysis of epoxides under continuous-flow conditions. A titania-zirconia supported molybdenum oxide catalyst demonstrated exceptional substrate compatibility, enabling the synthesis of β-amino alcohols in excellent yields with high catalyst durability. Characterization of the catalyst revealed the crucial role of the titania-zirconia ratio in optimizing its performance.
View Article and Find Full Text PDFWe describe the continuous-flow synthesis of (R)-tamsulosin, a blockbuster therapeutic drug employed for dysuria associated with urinary stones and benign prostatic hyperplasia, by utilizing sequential heterogeneous catalysis. Two heterogeneous catalysts have been developed for the synthesis, and the key step involves reductive amination of nitriles using dimethylpolysilane-modified Pd on activated carbon/calcium phosphate. Overall, (R)-tamsulosin was obtained in 60 % yield and 64 % ee (99 % ee after recrystallization) in a flow stream through four catalytic transformations without the need for the isolation or purification of any intermediates or byproduct.
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