Acid-Catalyzed Synthesis of α,β-Disubstituted Conjugated Enones by a Meyer-Schuster-Type Rearrangement in Allenols
作者:Benito Alcaide、Pedro Almendros、Sara Cembellín、Teresa Martínez del Campo
DOI:10.1002/adsc.201400928
日期:2015.3.23
A novel, direct and simple methodology to gain access to α,β‐disubstituted conjugated enones from α‐allenols in a sustainable metal catalysis context, considering the inexpensiveness and environmentally friendliness of iron(III) species and protons, has been developed.
N-Heterocyclic carbene/photo-cocatalyzed oxidative Smiles rearrangement: synthesis of aryl salicylates from <i>O</i>-aryl salicylaldehydes
作者:Zi-Hao Xia、Lei Dai、Zhong-Hua Gao、Song Ye
DOI:10.1039/c9cc09272b
日期:——
The N-heterocyclic carbene/photo-cocatalyzed oxidative Smiles rearrangement of O-aryl salicylaldehydes was developed. Both electron-deficient and electron-rich aryls worked well as migrating groups, giving the corresponding aryl salicylates in good yields. This reaction features formation of two new C-O bonds and one C-O bond cleavage via metal-free oxidation of the Breslow intermediate using oxygen
CBr<sub>4</sub> promoted intramolecular aerobic oxidative dehydrogenative arylation of aldehydes: application in the synthesis of xanthones and fluorenones
作者:Jing Tang、Shijun Zhao、Yuanyuan Wei、Zhengjun Quan、Congde Huo
DOI:10.1039/c7ob00080d
日期:——
promoted intramolecular aerobic oxidative dehydrogenative coupling reaction has been developed to provide a straightforward ring closure protocol for 2-aryloxybenzaldehydes to furnish xanthones. The reaction was performed under metal-, additive- and solvent-free conditions with good tolerance of functional groups. The present method is also applicable to the synthesis of fluorenones by using 2-arylbenzaldehydes
tert-Butoxide mediated cascade desulfonylation/arylation/hydrolysis of cyclic sulfonyimines using diaryliodonium salts: synthesis of diaryl ether derivatives bearing a 2-aldehyde group
作者:Xiaofei Qian、Jianwei Han、Limin Wang
DOI:10.1039/c6ra19313g
日期:——
Cascades of cyclic sulfonyimines mediated by tBuOK with diaryliodonium salts has been developed, giving the diaryl ethers in good yields. Furthermore, bulky ortho-substituted diaryl ethers with an aldehyde group can be obtained easily in comparision with metal-catalyzed protocols.