Aromatic functionalization

Catellani M (2005) Novel Methods of Aromatic Functionalization Using Palladium and Norbornene as a Unique Catalytic System. 14 21-54 ChataniN (2004) Selective Carbonylations with Ruthenium Catalysts. 11 173-195 Chatani N, see Kakiuchi F (2004) 11 45-79 Chlenov A, see Semmelhack MF (2004) 7 21-42 Chlenov A, see Semmelhack MF (2004) 7 43-70... 

Selective aromatic functionalization has been a permanent object of research since the ninenteenth century. Catalysis has offered a powerful tool to achieve this goal. Over the years we have worked out a complex catalytic system consisting of an inorganic compound such as a palladium salt and an organic molecule containing a strained double bond such as norbomene (1,2). We have seen that these two catalysts cooperatively react with an aromatic iodide, an alkyl iodide and a terminal olefin. The following equation reports an example (L = solvent and/or olefin) (3). 

In the last three decades, the development of transition metal catalyzed CC-coupling processes has revolutionized aromatic functional-... 

Catellani M (2005) Novel Methods of Aromatic Functionalization Using Palladium and Norbornene as a Unique Catalytic System. 14 21-54... 

If they are viewed as Pprodine analogues (see HI and LIll), an aromatic function at position 8 would be expected to enhance activity an 8-cinnamoyl group is detrimental in (LIll, R = Me) [146] but data on smaller aryl groups such as benzoyl has not been reported. 

Figure 5.4 Shielding/deshielding Zones for Common Non-aromatic Functional Groups...

Shifting and rearrangement of bonds within a molecule due to reaction with oxygen can result in the formation of compounds which impart color to fuel. These compounds often have some degree of aromatic functionality. The color imparted to the fuel is typically amber to brown. Some distillate fuels turn deep red in appearance while others appear pale green. 

To examine the utility of stationary phases composed of IL mixtures, a complex mixture of alcohols (both cyclic and aliphatic) and analytes with aromatic functionality were subjected to separation [41] on a stationary phase consisting of the [C4Cilm][Tf2N]. Under optimized conditions, the stationary phase was selective for most molecules, but exhibited poor resolution. Owing to the fact that most ILs containing the TfjN anion are weak hydrogen... 

Aromatic functional groups (benzene, naphthalene, pyridine rings) ... 

The XAD-8 resin separation of hydrophobic and hydrophilic components of WSOM was also employed by Sannigrahi et al. (2006). The 13C-NMR results indicated that WSOM in urban atmospheric particles is mostly aliphatic in nature (-95% C mass) with major contributions from alkyl and oxygenated alkyls (-80%), carboxylic acid (-10%), and aromatic functional groups (-4%). The authors also found that urban aerosol WSOC are only qualitatively similar to aqueous humic material in terms of functional group distribution. 

Quantitative FTIR data were combined with chemical and petrographic data for the 24 vitrinite concentrates and subjected to bivariate and multivariate statistical analyses in order to identify the effects of coal ification on the aliphatic and aromatic functional groups. 

From the limited data available, it seems that terminal alkynes can be efficiently reduced to the corresponding alkenes at mercury cathodes in (C4H9)4N+ electrolyte solutions. The cathodic reduction can be carried out in an organic-aqueous medium in which base related complications, associated with other electron-transfer reductions, can be avoided. Efficient reduction of alkenes has not proven possible. In competition, both benzenoid and alkyne functionalities are reduced. Selectivity can be improved by controlling the water content of the medium so that a terminal alkyne can be converted to an alkene in the presence of a benzenoid aromatic functionality. 

An aromatic functional group is one in which an aromatic ring is directly attached to the functional group ... 

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