113279-72-4

Upstream product

• 108-86-1 bromobenzene 
• 541-16-2 t-butyl malonate 
• 35207-75-1 di-tert-butyl diazomalonate 
• 2996-92-1 phenyl trimethylsiloxane 
• 108-90-7 chlorobenzene 

Relevant academic research and scientific papers

Rh(I)-catalyzed cross-coupling of α-diazoesters with arylsiloxanes

An Rh(I)-catalyzed cross-coupling of diazoesters with arylsiloxanes has been successfully achieved. This transformation is a new method for the construction of the C(sp3)-C(sp2) bond, thus providing an alternative synthesis of α-aryl esters. Rh(I)-carbene migratory insertion has been proposed to be involved in this coupling reaction. The reaction represents the first example of utilizing arylsiloxane as the coupling partner in the carbene-involved cross-coupling reactions.

PROCESS FOR PRODUCING PHOSPHONIUM BORATE COMPOUND, NOVEL PHOSPHONIUM BORATE COMPOUND, AND METHOD OF USING THE SAME

The invention relates to a phosphonium borate compound represented by Formula (I) (hereinafter, the compound (I)). The invention has objects of providing (A) a novel process whereby the compound is produced safely on an industrial scale, by simple reaction operations and in a high yield; (B) a novel compound that is easily handled; and (C) novel use as catalyst. ????????Formula (I) : (R1)(R2)(R3)PH·BAr4?????(I) wherein R1, R2, R3 and Ar are as defined in the specification. The process (A) includes reacting a phosphine with a) HCl or b) H2SO4 to produce a) a hydrochloride or b) a sulfate; and reacting the salt with a tetraarylborate compound. The compound (B) has for example a secondary or tertiary alkyl group as R1 and is easily handled in air without special attention. The use (C) is characterized in that the compound (I) is used instead of an unstable phosphine compound of a transition metal complex catalyst for catalyzing C-C bond, C-N bond and C-O bond forming reactions and the compound produces an effect that is equal to that achieved by the transition metal complex catalyst.

Palladium-catalyzed arylation of malonates and cyanoesters using sterically hindered trialkyl- and ferrocenyldialkylphosphine ligands

Palladium-catalyzed reactions of aryl bromides and chlorides with two common stabilized carbanions - enolates of dialkyl malonates and alkyl cyanoesters - are reported. An exploration of the scope of these reactions was conducted, and the processes were shown to occur in a general fashion. Using P(t-Bu)3 (1), the pentaphenylferrocenyl ligand (Ph5C5)Fe(C5H4)P(t-Bu) 2 (2), or the adamantyl ligand (1-Ad)P(t-Bu)2 (3), reactions of electron-poor and electron-rich, sterically hindered and unhindered aryl bromides and chlorides were shown to react with diethyl malonate, di-tertbutyl malonate, diethyl fluoromalonate, ethyl cyanoacetate, and ethyl phenylcyanoacetate. Although alkyl malonates and ethyl alkylcyanoacetates did not react with aryl halides using these catalysts, the same products were formed conveniently in one pot from diethylmalonate by cross-coupling of an aryl halide in the presence of excess base and subsequent alkylation.

Simple, highly active palladium catalysts for ketone and malonate arylation: Dissecting the importance of chelation and steric hindrance

A remarkably active catalyst system for α-arylation of ketones and malonates was developed by proposing that sterically hindered alkylphosphines would accelerate the catalytic reaction rates. We initially tested the bisphosphine ligand D'BPF (1,1'-bis-(di-tert-butylphosphino)ferrocene) for this palladium-catalyzed chemistry. This catalyst system led to fast reaction rates for reactions of aryl bromides with ketones, including room temperature chemistry in many cases. In some cases turnover numbers were 20 000. The catalyst also gave mild reactions with aryl chlorides with yields that were similar to the chemistry with aryl bromides. Independent synthesis of the arylpalladium enolate complexes with isobutyrophenone enolate showed that only one phosphorus of the bisphosphine ligand D'BPF was coordinated in the enolate complex. Thus, we tested sterically hindered alkylphosphine ligands for the ketone and malonate arylation process and found that P(t-Bu)3 gave exceptionally fast rates and high turnover numbers for these reactions. These results demonstrate several principles for the catalytic chemistry that we did not anticipate: palladium complexes of monophosphine ligands can activate aryl chlorides under mild conditions, and palladium enolates coordinated by certain monophosphines can undergo C-C bond-forming reductive elimination much faster than β-hydrogen elimination.