Chiral Aniline Synthesis via Stereospecific C(sp<sup>3</sup>)–C(sp<sup>2</sup>) Coupling of Boronic Esters with Aryl Hydrazines
作者:Venkataraman Ganesh、Adam Noble、Varinder K. Aggarwal
DOI:10.1021/acs.orglett.8b02615
日期:2018.10.5
is promoted by acylation of a hydrazinyl arylboronate complex, which triggers a N-N bond cleavage with concomitant 1,2-metalate rearrangement. Judicious choice of the acylating agent enabled the synthesis of ortho- and para-substituted anilines with essentially complete enantiospecificity from a wide range of boronic ester substrates.
描述了烷基硼酸酯和锂化芳基肼之间的对映体特异性偶联。该反应在无过渡金属条件下进行,并通过肼基芳基硼酸盐络合物的酰化促进,从而引发 NN 键断裂并伴随 1,2-金属酸盐重排。酰化剂的明智选择使得能够从广泛的硼酸酯底物合成具有基本完全对映专一性的邻位和对位取代的苯胺。
Toward Safer Processes for C−C Biaryl Bond Construction: Catalytic Direct C−H Arylation and Tin-Free Radical Coupling in the Synthesis of Pyrazolophenanthridines
pyrazolo[1,5-f]phenanthridine derivatives has been efficiently synthesized by a short, straightforward sequence. A tandem amine-exchange/heterocyclization of enaminones was successfully applied to the regioselective preparation of 1,5-diarylpyrazole intermediates with structure resemblance to relevant nonsteroidal anti-inflammatory drugs such as celecoxib or tepoxalin. The final key step, cyclization by intramolecular