A novel and mild Rh(iii)-catalyzed C-H activation/intramolecular condensation of 1-aryl-1H-pyrazol-5-amines with cyclic 2-diazo-1,3-diketones was developed, givingaccess to various important benzo[f]pyrazolo[1,5-a][1,3]diazepine scaffolds through sequential C-C/C-N bond formation in a one-pot procedure under additive- and oxidant-free conditions. Furthermore, 3-([1,1'-biphenyl]-2-ylamino)-2-ethoxycyclohex-2-enones
Transition-Metal-Free Dehydrogenation of Benzyl Alcohol for C–C and C–N Bond Formation for the Synthesis of Pyrazolo[3,4-<i>b</i>]pyridine and Pyrazoline Derivatives
electrocyclization, the aza-Diels–Alder reaction, and the formation of intramolecular C–N bonds. These positive outcomes would open up the possibility of producing biologically active pyrazolo[3,4-b]pyridine and pyrazoline derivatives through a variety of possible reactions.
已经开发了一系列级联反应,产生一系列具有吡唑/吡唑啉核的官能化芳族杂环化合物。该方法依赖于无金属脱氢过程来生产原位苯甲醛。然后让产生的苯甲醛与一些其他物质反应,包括苯乙酮、吡唑胺和苯肼。由这些底物产生的中间体经历了几个化学过程,包括电环化、aza-Diels-Alder 反应和分子内 C-N 键的形成。这些积极成果将开启通过各种可能的反应生产具有生物活性的吡唑并[3,4- b ]吡啶和吡唑啉衍生物的可能性。
Combinatorial synthesis of substituted pyrazolo-fused quinazolines by the Rh(iii)-catalyzed [5 + 1] annulation of phenyl-1H-pyrazol-5-amine with alkynoates and alkynamides
作者:Wei-Jung Chiu、Ting-Yen Chu、Chung-Ming Sun
DOI:10.1039/d4ob00516c
日期:——
developed for the first divergentsynthesis of pyrazolo[1,5-a]quinazolines through a [5 + 1] annulation reaction exclusively. The one-pot procedure is recognized for its broad substrate scope, functional group tolerance, and high atom economy. Mechanistic studies reveal the reaction pathway, addressing current limitations. Notably, this catalytic transition metal-assisted tandem annulation smoothly proceeds
开发了 Rh( III ) 催化的 C-H 活化/环化级联,用于仅通过 [5 + 1] 成环反应首次不同地合成吡唑并[1,5- a ]喹唑啉。一锅法因其广泛的底物范围、官能团耐受性和高原子经济性而受到认可。机理研究揭示了反应途径,解决了当前的局限性。值得注意的是,这种催化过渡金属辅助的串联环化通过取代的苯基-1H-吡唑-5-胺与炔酯或酰胺的反应顺利进行,其中单环碳由炔酸酯结构单元提供。这种转变凸显了过渡金属催化方法合成多种吡唑并[1,5- a ]喹唑啉骨架的潜力。
Ru(II)-catalyzed cyclization of 1-aryl-5-aminopyrazoles and α-diazolidinones for one-pot synthesis of benzopyrazole[1,3]diazepines in H2O/EtOH