Arylation, aromatic

In addition to aryl halides and triflates, organometallic reagents can be utilized for the catalytic arylation reaction. The rhodium-catalyzed arylation of arylpyridines proceeds with the use of tetraarylstannanes (Equation (67)).83 The ruthenium-catalyzed reaction of aromatic ketones with arylboronates affords the ortho-arylated aromatic ketones (Equation (68)).84... 

Substituents on imino nitrogen influence both reactivity and enantioselectivity in hydrogenation of imino compounds. Figure 1.32 shows two successful examples. An f-BINAPHANE-Ir complex effects asymmetric hydrogenation of A-aryl aromatic imines.On the other hand, an Et-DuPHOS-Rh complex (see Figure 1.2) is effective for hydrogenation of A-acyUiydrazones. ... 

Organic nitro compounds, RNO2, can be reduced to amines. The R may be either alkyl or aryl. Aromatic nitro compounds are easy to prepare and reduce. Their preparation utilizes a mixture of nitric acid and sulfuric acid to nitrate the aromatic ring. (However, multiple nitrations may occur, potentially causing problems.) The nitro group can be reduced with a... 

Intramolecular arylation. Aromatic substrates such as 1 on deprotonation (NaH) furnish stabilized enolates that undergo intramolecular arylation when heated... 

Very recently, Kakiuchi reported on the ruthenium-catalyzed arylation of C-H bonds using organoborane reagents. The reaction of aromatic ketones with arylboro-nates using a ruthenium catalyst resulted in the production of arylated aromatic ketones (Eq. 9.36) [50], This arylation reaction using arylboronates can be applied to a variety of aromatic ketones and arylboronates. The authors proposed that this reaction involves the oxidative addition of a C-H bond to a Ru(0) species. 

Ishikawa, T., Shimooka, K., Narioka, T., Noguchi, S., Saito, T., Ishikawa, A., Yamazaki, E., Harayama, T., Seki, H., Yamaguchi, K. Anomalous Substituent Effects in the Bischler-Napieralski Reaction of 2-Aryl Aromatic Formamides. J. Org. Chem. 2000, 65, 9143-9151. 

Organochlorine insecticides are chlorinated hydrocarbon compounds that fall into three basic structure classifications aryl (aromatic), carbocyclic, and heterocyclic. 

Arylation reactions of aromatic ketimines were developed, and in many cases the products of the reaction were isolated after subsequent hydrolysis. Therefore, these arylations constitute an indirect method for the preparation of arylated aromatic ketones, the direct functionalizations of which are often more difficult. Thus, direct arylation of imine 42 with sodium tetraphenylborate catalyzed by [RhCl(cod)]2 afforded a mixture of mono- and diarylated benzophenone imines (44 and 45) (Scheme 9.16) [53]. The formation of the corresponding amine 46 clearly indicated that 42 also acted as a hydride acceptor in this transformation. Most likely, the reaction occurs via initial coordination by the benzophenone imine to a phenylrho-dium intermediate followed by orfho-rhodation to afford the five-membered rhoda-cyde intermediate 47 (Scheme 9.16). Subsequent reductive elimination generates the monophenylated product 44 and a rhodium hydride, which then reduces imine 42 in the presence of ammonium chloride as proton donor to regenerate the catalytically active speties. 

Dialkylzinc is another common substrate in Pd-catalyzed couplings. An efficient ketone synthesis uses acid chlorides as starting material (Scheme 1-9). The use of PdCl2(dppf) offers high yields and is best in restricting the formation of benzaldehyde as a )8-elimination byproduct [117]. A-Aryl aromatic imine 34 can be obtained from aromatic iodides and aryl isocyanide 35 [118]. The proposed intermediate,... 

Amines are derivatives of ammonia. The alkyl derivatives of ammonia are called alkyl amines, and the aryl (aromatic) derivatives of ammonia are called aryl amines. These nitrogen-containing compounds are unique for their basicity. 

A process has been suggested that uses carbon monoxide, an aromatic dichloride and a diamine. As catalyst, a palladium complex is used, bis(triphenylphosphine)palladium(II)chloride. The catalyst induces the carbonylation of aryl aromatic chlorides. 

It is found that benzoin condensation of aldehydes are strongly catalysed by a PTC (quaternary ammonium cyanide in a two phase system). In a similar way, acyloin condensations are easily effected by stirring aliphatic or aromatic aldehydes with a quaternary catalyst (PTC), N-laurylthiazolium bromide in aqueous phosphate buffer at room temperature. The aromatic aldehydes reacted in a short time (about 5 min). However, aliphatic aldehydes require longer time (5-10 hr) for completion. Mixtures of aliphatic and aryl aromatic aldehydes give mixed a-hydroxy ketones. ... 

The Azo process is similar in nature to the Engels process, which uses an Azo compound (Azo compounds) are chemical compounds with the general formula R—N=N—R, where R and R can be either aryl (aromatic) or alkyl (aliphatic functional groups) rather than a peroxide. 

A carboamination reaction has been used for the construction of 1,4-benzodiazepines in good yield and diaster-eoselectivity. Wolfe et al. employed a substituted A-aryl aromatic amino compound as the precursor that after treatment with aryl bromide in the presence of the Pd catalyst, PPh2Cy ligand, and NaOt-Bu base under optimized conditions was transformed into substituted saturated benzodiazepine derivatives in good yield and diastereoselectivity (Scheme 40.17). °... 

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