Studies On Smiles Rearrangement And Terminal Alkyne Synthesis

This thesis includes two sections:The first section described the methodological research of Smiles rearrangement. As a classical name reaction, Smiles rearrangement is an intramolecular nucleophilic aromatic substitution reaction, and it has a widespread application among the drug synthesis. In this thesis, first, we described a cascade method that includes nucleophilic aromatic substitution reaction and Smiles rearrangement. The method shows good functional group tolerance with different electronic properties, providing efficient and practical access to dibenzoxazepinone architecture. Comparison of the products from cascade and step-by-step protocols demonstrates Smiles rearrangement is the pivotal step in the formation of heterocyclic products. Second, a one-pot Smile rearrangement has been developed as a useful protocol for the straightforward synthesis of diverse N-aryl nicotinamides. This method also provides chemoselective access toward diarylamines based on the different substitutions of the amide group.In the second section, we described terminal alkyne preparation methodology research. Terminal alkynes are versatile functional groups that play very important roles in modern organic chemistry. It would be very significant to improve the synthetic methods. An efficient method of preparing various terminal alkynes from 1,1-dibromo-1-alkenes by using TBAF and TBAB/K2CO3 as a base and triphenylphosphane as a reductant was developed. This method is strong base and low/high temperatures free, and can tolerate a broad range of substrates.