Biswal Priyabrata, Samser Shaikh, Nayak Prakash, Chandrasekhar Vadapalli, Venkatasubbaiah Krishnan
School of Chemical Sciences, National Institute of Science Education and Research (NISER), Bhubaneswar, HBNI, Bhubaneswar-752050, Odisha, India.
Tata Institute of Fundamental Research Hyderabad, Gopanpally, Hyderabad-500046, Telangana, India.
J Org Chem. 2021 May 7;86(9):6744-6754. doi: 10.1021/acs.joc.1c00476. Epub 2021 Apr 26.
A novel cobalt(II)porphyrin-mediated acceptorless dehydrogenation of methanol is reported for the first time. This methodology has been applied for the coupling of a variety of ketones with methanol to produce 1,5-diketones along with H and HO as the environment friendly byproducts. This paradigm was also demonstrated for a one-pot synthesis of substituted pyridines using a sequential addition protocol where the 1,5-diketones were generated in situ. From many experiments including those involving deuterium labeling, it is proposed that protonated cobalt(II)porphyrin methoxide complex acts as an intermediate to generate formaldehyde along with a metal hydride.
首次报道了一种新型钴（II）卟啉介导的甲醇无受体脱氢反应。该方法已用于多种酮与甲醇的偶联反应，生成1,5-二酮以及氢气和水作为环境友好型副产物。通过连续添加方案一锅法合成取代吡啶也证明了这一范例，其中1,5-二酮是原位生成的。通过包括氘标记实验在内的许多实验，提出质子化的钴（II）卟啉甲醇盐配合物作为中间体生成甲醛和金属氢化物。
