One-pot Synthesis of Dibenzofurans via SNAr and Subsequent Ligand-free Palladium-catalyzed Intramolecular Aryl-aryl Cross-coupling Reactions under Microwave Irradiation
Arylmethanesulfonates are convenient latent phenols in the nucleophilic aromatic substitution reaction
作者:Christopher J. Dinsmore、C.Blair Zartman
DOI:10.1016/s0040-4039(99)00660-7
日期:1999.5
protecting group for a phenol is conveniently unmasked under the conditions of the SNAr reaction with an activated aryl halide, producing diarylether products directly. The method is advantageous when the preparation of a phenol substrate requires O-protection, since the selection of the robust methanesulfonate as a latent phenol obviates a deprotection step prior to the SNAr reaction.
苯酚的甲磺酰基保护基在S N Ar反应条件下与活化的芳基卤化物方便地被掩盖,直接生产二芳基醚产物。该方法是有利的,当一个酚基片的制备需要ø -防护,由于鲁棒甲磺酸盐作为潜苯酚消除脱保护之前,在S步骤的选择Ñ的Ar反应。
Synthesis and enantioselective hydrogenation of seven-membered cyclic imines: substituted dibenzo[b,f][1,4]oxazepines
Highlyenantioselective hydrogenation of seven-membered cyclic imines, substituted dibenzo[b,f][1,4]oxazepines, was achieved, with up to 94% ee, by using the [Ir(COD)Cl](2)/(S)-Xyl-C(3)*-TunePhos complex as the catalyst in the presence of morpholine-HCl.
Synthesis and chemistry of the phenoxasilins and dihydro-dibenzo-oxasilepins
作者:V.H.T. Chang、J.Y. Corey
DOI:10.1016/s0022-328x(00)83978-9
日期:1980.5
sila-functional and carbo-functional phenoxasilins from diphenyl ether and o,o′-dibromodiphenyl ether precursors is described. Tricyclic oxasilepins are formed from o,o′-dibromobenzylphenyl ether by metallation with n-BuLi followed by reaction with dichlorosilanes as well as by ringexpansion of an appropriate phenoxasilin. Reactions at the silicon center and at the ring methylene carbon of the oxasilepins are
Csp<sup>2</sup>–Csp<sup>2</sup> and Csp<sup>2</sup>–N Bond Formation in a One-Pot Reaction between <i>N</i>-Tosylhydrazones and Bromonitrobenzenes: An Unexpected Cyclization to Substituted Indole Derivatives
A novel, sequential, palladium-catalyzed, cross-coupling reaction using N-tosylhydrazone and bromonitrobenzene derivatives followed by reductive cyclization has been developed. This transformation providing an efficient route to unexpected N-arylindole derivatives involves, in a one-pot reaction, the formation of one Csp2–Csp2 bond and two Csp2–N bonds together with the cleavage of one Csp2–heteroatom
Palladium-Catalyzed Synthesis of Six-Membered Benzofuzed Phosphacycles via Carbon–Phosphorus Bond Cleavage
作者:Katsuaki Baba、Mamoru Tobisu、Naoto Chatani
DOI:10.1021/ol503252t
日期:2015.1.2
The palladium-catalyzed synthesis of dibenzofused six-membered phosphacycles via carbon–phosphorus bond cleavage is developed. This method is compatible with a range of functional groups, such as esters, amides, and carbamates, which is in sharp contrast to the limitations of the classical method using organolithiumreagents.