25570-02-9Relevant articles and documents
Discovery and mechanistic investigation of Pt-catalyzed oxidative homocoupling of benzene with PhI(OAc)2
Abu-Omar, Mahdi M.,Nabavizadeh, S. Masoud,Niroomand Hosseini, Fatemeh,Park, Chan,Wu, Guang
supporting information, p. 2477 - 2486 (2020/03/05)
We present a Pt-catalyzed direct coupling of benzene to biphenyl. This catalytic reaction employs a cyclometalated platinum(ii) complex [PtMe(bhq)(SMe2)] (bhq = benzo[h]quinolate) with PhI(OAc)2 as an oxidant and does not require an acid, a co-catalyst or a solvent. The reaction kinetics and characterization of potential catalytic species are reported. The reaction is first-order in Pt and second-order in benzene, which implicates the second C-H activation step as rate-determining. A Pt(ii)/Pt(iv) catalytic cycle is suggested. The reaction commences by oxidation of the Pt(ii) complex to give the platinum(iv) species [Pt(bhq)(SMe2)(OAc)2](OAc) followed by C-H activation of benzene to afford the intermediate [PtPh(bhq)(SMe2)(OAc)](OAc) concurrently with the release of HOAc. A second benzene molecule reacts similarly to give the diphenyl intermediate [PtPh2(bhq)(SMe2)](OAc). C-C bond forming reductive elimination ensues to regenerate Pt(ii) and complete the catalytic cycle. The proposed mechanism has been examined by DFT computations, which provide support to experimental findings.
Cobalt-catalyzed electrophilic amination of arylzincs with N-chloroamines
Qian, Xin,Yu, Zailu,Auffrant, Audrey,Gosmini, Corinne
supporting information, p. 6225 - 6229 (2013/07/05)
Roles reversed: An efficient cobalt-catalyzed electrophilic amination of arylzinc reagents has been achieved. A variety of functionalized arylzincs and N-chloroamines were coupled under mild conditions (see scheme). Both secondary and tertiary arylamines were obtained in moderate to excellent yields. Copyright
Combining Homogeneous Catalysis with Heterogeneous Separation using Tunable Solvent Systems
Blasucci, Vittoria M.,Husain, Zainul A.,Fadhel, Ali Z.,Donaldson, Megan E.,Vyhmeister, Eduardo,Pollet, Pamela,Liotta, Charles L.,Eckert, Charles A.
experimental part, p. 3932 - 3938 (2010/08/04)
Tunable solvent systems couple homogeneous catalytic reactions to heterogeneous separations, thereby combining multiple unit operations into a single step and subsequently reducing waste generation and improving process economics. In addition, tunable solvents can require less energy than traditional separations, such as distillation. We extend the impact of such solvents by reporting on the application of two previously described carbon dioxide tunable solvent systems: polyethylene glycol (PEG)/organic tunable solvents (POTS) and organic/aqueous tunable solvents (OATS). In particular, we studied: (1) the palladium catalyzed carbon-oxygen coupling of 1-bromo-3,5-dimethylbenzene and o-cresol to potassium hydroxide to produce o-tolyl-3,5-xylyl ether and 1-bromo-3,5-di-tert-butylbenzene to potassium hydroxide to produce 3,5-di-tert-butylphenol in PEG400/1,4-dioxane/water and (2) the rhodium-catalyzed hydroformylation of p-methylstyrene in water/ acetonitrile to form 2-(p-tolyl) propanal. In addition, we introduce a novel tunable solvent system based on a modified OATS where propane replaces carbon dioxide. This represents the first use of propane in a tunable solvent system.
