Synthesis of Thiophene-Substituted Ketones via Manganese-Catalyzed Dehydrogenative Coupling Reaction.

This study reports an efficient and green one-step method for synthesizing thiophene-substituted ketones from 2-thiophenemethanol and ketones via dehydrogenative coupling using manganese complexes as catalysts. The manganese complex demonstrated a broad applicability under mild conditions and extended the range of usable substrates. Utilizing this strategy, we carried out an efficient and diverse reaction of ketones with 2-thiophenemethanol, and successfully synthesized a series of thiophene-substituted saturated ketones and α, ß-unsaturated ketones in good isolated yields.

Synthesis of Tetrahydro-ß-carbolines by a Manganese-Catalysed Oxidative Pictet-Spengler Reaction.

Herein, an efficient and green procedure for the synthesis of tetrahydro-ß-carbolines via dehydrogenative coupling of alcohols with tryptamines is reported. The reaction was carried out under mild conditions in the presence of a catalytic amount of the iPr PNP-Mn catalyst and a weak base (Na2 CO3 ). This method tolerated a variety of benzylic and aliphatic alcohol substrates with different functional groups and afforded diverse products in good to excellent isolated yields using tryptamines. Using this strategy, we successfully synthesised pharmaceutical molecules harman, harmaline, and harmine in a concise manner.