We developed a chromium-catalyzed, photochemical, and linear-selective alkylation of aldehydes with alkylzirconium species generated in situ from a wide range of alkenes and Schwartz’s reagent. Photochemical homolysis of the C–Zr bond afforded alkyl radicals, which were then trapped by a chromium complex catalyst to generate the alkylchromium(III) species for polar addition to aldehydes. The reaction
Electronictuning: Nitroxylradical 1 is shown to be an efficient catalyst for the oxidation of secondary alcohols, and promotes oxidation through an oxoammonium species which is highly reactive because of the adjacent electron‐withdrawing ester groups. Chemoselectiveoxidation of benzylic alcohols in the presence of aliphatic alcohols is observed and is proposed to proceed by a rate‐determining hydride
A catalyticenantioselective addition reaction of alkylzirconium species to aromatic aldehydes is reported. The reaction, facilitated by a chiral nonracemic diol ligand complex with Ti(OiPr)4, proceeds under mild and convenient conditions, and no premade organometallic reagents are required since the alkylzirconium nucleophiles are generated in situ by hydrozirconation of alkenes with the Schwartz
approach for the distalconstruction of a C(sp3)−SCF2R bond on aliphaticalcoholsenabled by 1,5-hydrogen-atom transfer (HAT) was developed. In the presence of a hypervalent iodine (PIDA) and readily available ArSO2SCF2R reagents, this transition metal-free approach allowed the remote functionalization of a broad variety of alcohols with emergent and high added-value SCF2R moieties (R=H, F, CO2Et and
开发了一种通过 1,5-氢原子转移 (HAT) 在脂肪醇上构建 C( sp 3 )-SCF 2 R 键的方法。在高价碘 (PIDA) 和现成的 ArSO 2 SCF 2 R 试剂存在的情况下,这种不含过渡金属的方法可以远程官能化具有新兴和高附加值 SCF 2 R 部分的多种醇(R= H、F、CO 2 Et 和 PO(OEt) 2 ) 在蓝光照射下。
Deaminative Addition of Alkylpyridinium Salt to Aldehyde
作者:Yu Huang、Zhengqiang Liu、Wenbo H. Liu
DOI:10.1021/acs.orglett.3c01724
日期:2023.7.7
Here we show that a primary amine can engage in the nucleophilic addition to an aldehyde to synthesize an alcohol following preactivation of the amine. The enabling reagent for this radical-polar crossover process is CrCl2. This reaction is selective for aldehydes and compatible with numerous functional groups, which are not tolerated under classical Grignard-type conditions. Complementary to the well-established