Zhao Mingxin, Chen Miao, Wang Tian, Yang Shuhan, Peng Qian, Tang Pingping
State Key Laboratory and Institute of Elemento-Organic Chemistry, Nankai University, 300071, Tianjin, China.
Haihe Laboratory of Sustainable Chemical Transformations, 300192, Tianjin, China.
Nat Commun. 2023 Jul 31;14(1):4583. doi: 10.1038/s41467-023-40180-6.
Despite the growing importance of fluorinated organic compounds in pharmaceuticals, agrochemicals, and materials science, the introduction of fluorine into organic molecules is still a challenge, and no catalytic fluorocarbonylation of aryl/alkyl boron compounds has been reported to date. Herein, we present the development of palladium and phosphine synergistic redox catalysis of fluorocarbonylation of potassium aryl/alkyl trifluoroborate. Trifluoromethyl arylsulfonate (TFMS), which was used as a trifluoromethoxylation reagent, an easily handled and bench-scale reagent, has been employed as an efficient source of COF. The reaction operates under mild conditions with good to excellent yields and tolerates diverse complex scaffolds, which allows efficient late-stage fluorocarbonylation of marked small-molecule drugs. Mechanistically, the key intermediates of labile Brettphos-Pd(II)-OCF complex and difluoro-Brettphos were synthesized and spectroscopically characterized, including X-ray crystallography. A detailed reaction mechanism involving the synergistic redox catalytic cycles Pd(II)/(0) and P(III)/(V) was proposed, and multifunction of phosphine ligand was identified based on F NMR, isotope tracing, synthetic, and computational studies.
尽管氟化有机化合物在制药、农用化学品和材料科学中日益重要,但将氟引入有机分子仍然是一项挑战,并且迄今为止尚未有关于芳基/烷基硼化合物的催化氟羰基化反应的报道。在此,我们展示了钯和膦协同氧化还原催化芳基/烷基三氟硼酸钾的氟羰基化反应的进展。三氟甲磺酸芳基酯(TFMS),作为一种三氟甲氧基化试剂,一种易于操作且适用于实验室规模的试剂,已被用作COF的有效来源。该反应在温和条件下进行,产率良好至优异,并且能够耐受多种复杂的骨架结构,这使得能够对标记的小分子药物进行高效的后期氟羰基化反应。从机理上讲,合成了不稳定的Brettphos-Pd(II)-OCF配合物和二氟-Brettphos的关键中间体,并通过光谱进行了表征,包括X射线晶体学。提出了一个涉及Pd(II)/(0)和P(III)/(V)协同氧化还原催化循环的详细反应机理,并基于氟核磁共振、同位素示踪、合成和计算研究确定了膦配体的多功能性。