reaction of secondary and tertiary benzyl alcohols activated by 2,4,6-trichloro-1,3,5-triazine (TCT) with aldehydes in the presence of NiCl2·dmg as a precatalyst in ethylene glycol afforded ethers at roomtemperature. A selective C–O vs C–C bond formation was observed for the secondary and tertiary benzyl alcohols in comparison with primary ones.
Iodine catalysed synthesis of unsymmetrical benzylic ethers by direct cross-coupling of alcohols
作者:Balamphrang Kharrngi、Grace Basumatary、Ghanashyam Bez
DOI:10.1016/j.tetlet.2021.153370
日期:2021.9
Although symmetrical ethers can be synthesized easily fromalcohols, synthesis of unsymmetricalethers by dehydrative cross-coupling of alcohols is still a challenge. While dehydrative cross-coupling is environmentally appealing due to formation of water as the only byproduct, the chances for formation of symmetrical ethers always exist. The existing transition metal based methods give good selectivity