| Suzuki-Miyaura,previously known as Suzuki,cross-coupling is an efficient tool for carbon-carbon bond formation under mild conditions and it plays an important role in organic synthesis.The reaction features a number of advantages such as tolerance to a variety of functional groups,being less sensitive to steric bulkiness, high yielding,availability of aryl boronic acids and related equivalent boron reagents, and stability of the boron reagents toward moisture.The protocol has been widely adopted in synthesis of fine pharmaceutical intermediates.Palladium catalyst is a critical factor for successful Suzuki cross-coupling. Selection of an appropriate catalyst is not only to promote the reaction under milder conditions but also to improve the product yield.In some cases,an active catalyst can make a reaction occurring otherwise it might be impossible to take place.Palladium and phosphine ligands constitute an important catalyst type for Suzuki cross-coupling in addition to the palladium-N-heterocyclic carbene complexes.An electron-rich and sterically bulky phosphine is the core component of a high-performing catalyst.This PhD thesis mainly summarizes the original results on studies of aromatic amide-derived phosphines(Aphos),including the precatalyst system consisting of Aphos and Pd(OAc)2 and the applications for promoting room temperature Suzuki cross-coupling of aryl chlorides and aryl/vinyl bromides,respectively,with aryl/vinyl boronic acids,and alkyl boranes.Chapter 1 briefly introduces the recent progress in Suzuki cross-coupling reaction,covering advances made in development of high-performing catalysts and in applications of different types of substrates and catalysts in organic synthesis.Chapter 2 presents our studies on aromatic amide-derived phosphine(Aphos) applied to room temperature Suzuki cross-coupling of unactivated aryl chlorides with aryl boronic acids.By following the "self-assisted molecular editing"(SAME) protocol first established in our labs,a number of Aphos ligands were efficiently prepared from a single starting material and they were screened for catalytic efficacy, leading to the discovery of the best-performing Aphos appended with a 3-nitrophenyl group at the C4 position.Combination of this Aphos with Pd(OAc)2 offers a precatalyst for successful cross-coupling of unactivated aryl chlorides with aryl boronic acids at room temperature.The reactions took place under mild basic conditions to produce the products in high yields.The following Chapter 3 summarizes the results of room temperature Suzuki cross-coupling of vinyl boronic acids with aryl and vinyl bromides by using the Aphos possessing a 2,6-dimethylphenyl group at the C4 position as the ligand to Pd(OAc)2.Various aryl bromides including very inactive and sterically hindered substrates underwent smooth reactions with vinyl boronic acids to furnish the products in excellent yields.For activated aryl chlorides,similar outcome was obtained for the room temperature cross-coupling with vinyl boronic acids.Finally,the room temperature Suzuki cross-coupling reactions were extended to aryl and vinyl bromides with alkyl boranes under the same reaction conditions optimized for the reactions of vinyl boronic acids.The Aphos-Pd(OAc)2 system was proved very efficient for the coupling of alkyl boranes and the results are collected in Chapter 4.At the temperature of 50℃,a variety of aryl chlorides successfully coupled with alkyl boranes as well.The experimental section,compound characterization data,and references are found at the end of the thesis,together with copies of both 1H and 13C NMR spectra of the new compounds synthesized during this thesis research.
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