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A new class of chiral phosphines belonging to the P-aryl-2-phosphabicyclo octane family (PBO) is prepared by enantioselective synthesis starting from lactate esters and 2,2-dimethylcyclopentanone enolate. A substantial effort was invested to probe the relationship between catalyst purity and enantioselectivity.

A method is developed for auxiliary-directed, palladium-catalyzed [beta]-arylation and alkylation of [sp.sup.3] and [sp.sup.2] C-H bonds in carboxylic acid derivatives. 8-Aminoquinoline auxiliary has produced the best results for alkylation of [sp.sup.3] and [sp.sup.2] C-H bonds, where functional group tolerance is observed and amino- and hydroxyl-acid derivatives are functionalized.

Microfluidics is used for implementing genetic algorithms (GA) for discovering new homogeneous catalysts by using the oxidation of methane by molecular oxygen as a model system. The Pt/Fe system has shown the compatibility of iron with the entire catalytic cycle and the approach of GA-guided evolution has the potential to accelerate the discovery in catalysis and other areas

A general method is developed for copper-catalyzed deprotonative dimerization of arenes by using oxygen as the terminal oxidant. The electron-rich and electron-poor heterocycles as well as electron-poor arenes are reactive and the method is tolerant to functionalities like nitro, cyano, dialkylamino and ester groups.

A general method is developed for in situ trapping of arylmetal intermediates by halogen, sulfur, ketone and aldehyde electrophiles, which has produced the functionalization of the most acidic position in arene. [K.sub.3]P[O.sub.4] base is used for functionalizing pentafluorobenzene, benzothiazole and benzoxazole.

A general method is developed for copper-catalyzed arylation of [sp.sup.2] C-H bonds with p[K.sub.a]'s below 35. Electron-poor arenes possessing at least two electron-withdrawing groups on a benzene ring is arylated and two arylcopper-phenanthroline complex intermediates are prepared independently.

The development a palladium-catalyzed benzamide sequence ortho-arylation/rection with [(C[F.sub.3]CO).sub.2]O for convenient one-pot synthesis of ortho-arylated benzonitriles and fluorenone derivatives is reported. The N-propyl benzamides is converted to fluorenones while N-cyclohexyl benzamides yield benzonitrile derivatives.

The article explains the development and efficiency of a new approach for direct arylation of heterocycle C-H bonds by aryl halides, using copper as a catalyst. The technique can be widely used for organic synthesis due to its readily available starting materials.

A study conducted demonstrates that anilides possessing a number of different acyl groups could be arylated by aryl iodides by using palladium catalysis. The arylation products could be converted to phenanthridines by the reaction with trifluoroacetic anhydride.

Two new palladium-catalyzed methods are developed for the direct ortho-arylation of free benzoic acids. Inter- and intramolecular isotope effects for the benzoic acid arylation by aryl chlorides are determined and are found to be the same with a magnitude of 4.4 pointing toward heterolytic C-H cleavage as the turnover-limiting step.

A strategy in which C-H activation reactions promoted by Pd(II) are combined with beta-heteroatom elimination to create a catalytic cycle and achieve the arylation of haloolefins is described. The catalytic cycle can be subdivided into four parts, which includes C-H activation.

A general method is described for the copper-catalyzed arylation and alkenylation of polyfluorobenzene C-H bonds. The results are obtained by using a combination of copper iodide catalyst, phenanthroline ligand, aryl bromide or aryl iodide coupling partner, and DMF or DMF/xylene mixed solvent.

A new arylation process based on C-H is developed and it allows for the beta-arylation of carboxylic acid derivatives and gamma-arylation of amine derivatives. Efforts are underway to extend this methodology to arylation of esters and alkenylation of amides and esters.

A general method for synthesis of 1,2-bis-trifluoromethylthioarenes has been developed. Arynes generated from silyl aryl triflates or halides react with bis(trifluoromethyl)disulfide to afford 1,2-bis-trifluoromethylthioarenes. Aryl, alkyl, ester, halide, and methoxy functionalities are compatible with reaction conditions. Use of bis(perfluoroaryl)disulfides gave moderate yields of aryne disulfenylation or cyclization to fluorinated dibenzothiophenes. [ABSTRACT FROM AUTHOR]

Phosphine-iminophosphorane palladium complexes were synthesized and studied as catalysts for ethylene polymerization. The effect of the substituents on the phosphine and iminophosphorane moieties was investigated. Catalyst 15 promoted the conversion of ethylene to moderate molecular weight linear polyethylene ( M n ≈ 14000 g/mol, branches/1000C ≈ 7). This catalyst proved to be stable at temperatures up to 100 °C with a turnover frequency of 2100 h-1. [ABSTRACT FROM AUTHOR]

The palladium diphosphine complex 4 converts ethylene to hyperbranched unsaturated oligomers (Mn ≈ 330 g/mol) at 22 °C. In addition to the high stability of this catalyst observed at temperatures up to 75 °C, an increase of the reaction temperature leads to a decrease in branching densities of the oligomers, in sharp contrast to the palladium and nickel diimine catalyst systems. One-pot oligomerizations/hydrogenations were carried out to form hyperbranched saturated oligomers. [ABSTRACT FROM AUTHOR]

Studies on chiral phosphine catalysis for enantioselective acylation have revealed exceptional catalysts based on the 2-phosphabicyclo(3.3.0)octane skeleton. The first member of this catalyst family was observed to activate m-chlorobenzoic anhydride for aroyl transfer in the kinetic resolution of phenyl tert-butyl carbinol. It is interesting to note that the reaction was more than 100 times faster than with the original catalyst. Modifications of catalyst structure that might enhance phosphorus diastereoselectivity in the cyclization were examined.

The dual activation method using magnesium bromide (MgBr2) and a tertiary amine activated the hindered pivalic anhydride and converted it into a pivalate ester in 99% yield after 22 hrs. at room temperature. The amine and MgBr2 were mixed with linalool prior to reaction with the anhydride to minimize decomposition of the enolizable anhydride. Phthalic anhydrides and 1-methylcyclohexanol gave the highest yield although the reaction was slower than the corresponding benzoylations.

Silylaryl bromides and iodides can be prepared in one step from commercially available starting materials. Arynes can be generated from these compounds under conditions nearly identical to those employed for silylaryl triflates. Three distinct transformations, ortho-arylation of N-tritylanilines, intermolecular addition of arynes to amides, and reaction of ureas with arynes, were shown to be successful for the new aryne precursors. The main advantage of silylaryl halides relative to silyl aryl triflates is their one-step preparation from commercially available starting materials. [ABSTRACT FROM AUTHOR]

An operationally simple and general method for copper-catalyzed, aminoquinoline-assisted amination of βC(sp2)-H bonds of benzoic acid derivatives is reported. The reaction employs Cu(OAc)2 or (Cu0H)2C03 catalysts, an amine coupling partner, and oxygen from air as a terminal oxidant. Exceptionally high generality with respect to amine coupling partners is observed. Specifically, primary and secondary aliphatic and aromatic amines, heterocycles, such as indoles, pyrazole, and carbazole, sulfonamides, as well as electron-deficient aromatic and heteroaromatic amines are competent coupling components. [ABSTRACT FROM AUTHOR]

Conspectus: In recent years, carbon-hydrogen bond functionalization has evolved from an organometallic curiosity to a tool used in mainstream applications in the synthesis of complex natural products and drugs. The use of C-H bonds as a transformable functional group is advantageous because these bonds are the most abundant functionality in organic molecules. One-step conversion of these bonds to the desired functionality shortens synthetic pathways, saving reagents, solvents, and labor. Less chemical waste is generated as well, showing that this chemistry is environmentally beneficial. This Account describes the development and use of bidentate, monoanionic auxiliaries for transition-metal-catalyzed C-H bond functionalization reactions. The chemistry was initially developed to overcome the limitations with palladium-catalyzed C-H bond functionalization assisted by monodentate directing groups. By the use of electron-rich bidentate directing groups, functionalization of unactivated sp³ C-H bonds under palladium catalysis has been developed. Furthermore, a number of abundant base-metal complexes catalyze functionalization of sp² C-H bonds. At this point, aminoquinoline, picolinic acid, and related compounds are among the most used and versatile directing moieties in C-H bond functionalization chemistry. These groups facilitate catalytic functionalization of sp² and sp³ C-H bonds by iron, cobalt, nickel, copper, ruthenium, rhodium, and palladium complexes. Exceptionally general reactivity is observed, enabling, among other transformations, direct arylation, alkylation, fluorination, sulfenylation, amination, etherification, carbonylation, and alkenylation of carbon-hydrogen bonds. The versatility of these auxilaries can be attributed to the following factors. First, they are capable of stabilizing high oxidation states of transition metals, thereby facilitating the C-H bond functionalization step. Second, the directing groups can be removed, enabling their use in synthesis and functionalization of natural products and medicinally relevant substances. While the development of these directing groups presents a significant advance, several limitations of this methodology are apparent. The use of expensive second-row transition metal catalysts is still required for efficient sp³ C-H bond functionalization. Furthermore, the need to install and subsequently remove the relatively expensive directing group is a disadvantage. [ABSTRACT FROM AUTHOR]

A method for aminoquinoline-directed, cobalt-promoted dimerization of benzamides has been developed. Reactions proceed in ethanol solvent in the presence of Mn(OAc)2 cocatalyst and Na2CO3 base and use oxygen as a terminal oxidant. Bromo, iodo, nitro, ether, and ester moieties are compatible with the reaction conditions. Cross-coupling of electronically dissimilar aminoquinoline benzamides proceeds with modest yields and selectivities. [ABSTRACT FROM AUTHOR]

A methodfor cobalt-catalyzed, aminoquinoline-directed ortho-functionalization of sp2C–H bondswith alkenes has been developed. Reactions proceed at room temperaturein trifluoroethanol solvent, use oxygen from air as an oxidant, andrequire Mn(OAc)3as a cocatalyst. Benzoic, heteroaromatic,and acrylic acid aminoquinoline amides react with ethylene as wellas mono- and disubstituted alkenes affording products in good yields.Excellent functional group tolerance is observed; halogen, nitro,ether, and unprotected alcohol functionalities are compatible withthe reaction conditions. [ABSTRACT FROM AUTHOR]

A method for direct, auxiliary-assisted alkoxylation and phenoxylation of β-sp2C–H bonds of benzoic acid derivatives and γ-sp2C–H bonds of amine derivatives is reported. The reaction employs (CuOH)2CO3catalyst, air as an oxidant, phenol or alcohol coupling partner, DMF, pyridine, or DMPU solvent, and K2CO3, tetramethylguanidine, or K3PO4base at 70–130 °C. [ABSTRACT FROM AUTHOR]

A method for direct, transition-metal-free ortho-arylation of anilines by aryl chlorides, bromides, fluorides, and triflates has been developed. This methodology provides the most direct approach to 2-arylanilines since no protecting or directing groups on nitrogen are required. The arylation is functional-group tolerant, with alkene, ether, trifluoromethyl, dimethylamino, carbonyl, chloro, and cyano functionalities tolerated. Phenylation of enantiopure binaphthyldiamine affords a product with >99% ee. [ABSTRACT FROM AUTHOR]