Design and synthesis of novel indoline-(thio)urea hybrids

Abstract

A series of novel indoline-(thio)urea were designed and prepared using indoline(s) as a new platform and tested as organocatalysts in the Michael and Morita-Baylis-Hillman reactions. Most of the compounds were found to be very active catalysts although they did not promote the enantioselectivity. As agents for the conversion of thiocarbonyl compounds into carbonyl compounds, potentials of PIFA and DDQ were also displayed. Furthermore, DFT calculations rationalized the experimentally observed non-enantioselectivity of the catalysts.

Cu-catalyzed aerobic oxidative dehydrogenation of tertiary indolines to indoles using azo/hydrazide redox

“…The dehydrogenation of saturated N-heterocycles to their corresponding N-heteroaromatic compounds is a fundamental and fascinating transformation in synthetic, materials, and medicinal chemistry. 1 The dehydrogenation of saturated N-heterocycles is conventionally conducted using stoichiometric amounts of oxidants such as DDQ, 2 metal oxides, 3 and others, 4 however, these methods are less attractive because of the toxicity and waste disposal associated with the oxidants. In recent years, transition metal-catalyzed acceptorless dehydrogenation has been regarded as a promising route for the synthesis of N-heteroaromatic compounds, 5 because acceptorless dehydrogenation requires no stoichiometric oxidants and produces only molecular hydrogen as a byproduct.…”