The author of 《Xantphos as a Branch-Selective Ligand for the Acyclic sec-Alkyl Negishi Cross-Coupling of Heteroaryl Halides》 were Cherney, Alan H.; Hedley, Simon J.; Mennen, Steven M.; Tedrow, Jason S.. And the article was published in Organometallics in 2019. Computed Properties of C5H5BrN2 The author mentioned the following in the article:
We present the application of the common bidentate phosphine ligand Xantphos toward the highly selective Negishi cross-coupling of heteroaryl halides and acyclic sec-alkyl organozinc reagents to prepare pharmaceutically relevant motifs. Branched-to-linear ratios of >100:1 can be achieved for several substrates relevant to the pharmaceutical industry, and tolerance of certain acidic protons is exhibited. A high-throughput experimentation approach was taken to rapidly compare Xantphos Pd G3 to other selective Negishi coupling catalysts, leading to sep. reactivity profiles for each methodol. The utility of Xantphos Pd G3 was demonstrated through the scale-up and isolation of a complex pyridine building block. In the experimental materials used by the author, we found 6-Bromopyridin-3-amine(cas: 13534-97-9Computed Properties of C5H5BrN2)
6-Bromopyridin-3-amine(cas: 13534-97-9) belongs to anime. To avoid the problem of multiple alkylation, methods have been devised for “blocking” substitution so that only one alkyl group is introduced. The Gabriel synthesis is one such method; it utilizes phthalimide, C6H4(CO)2NH, whose one acidic hydrogen atom has been removed upon the addition of a base such as KOH to form a salt.Computed Properties of C5H5BrN2