C-H Functional Groups

MSCE 36,421-6(1951)(Detg the true C,H, functioning group by using Ag benzoate)... 

An aldehyde contains the characteristic —C—H functional group in its molecules. Figure 7.26 shows the bonding in formaldehyde, which is the simplest organic... 

Nj = number of C-H atomic groups / bonded to at least one functional group or atom in tbe molecule of interest ny= number of different functional groups or atoms in tbe molecule of interest... 

Stage 1 Difunctional monomers A, with functional groups called c, react by an alternating polyaddition reaction with an excess mixture of difunctional D and trifunctional T monomers, which all have the same functional groups, called h (and thus are equally reactive), to (mainly) h-terminated prepolymer PI. In some calculations tetra-functional Q monomers with equally reactive h functional groups were present as well. 

Reduction with [Cp2Zr(H)Cl]n (1) of common C=X functional groups such as aldehydes, ketones, nitriles and related functionality is also possible. 

Directed sp2 -C-H functionalizations enable the catalytic transformation to be controlled by a coordinating group, often leading to ort o-functionalized products. These are extremely popular processes, and a selection of these reactions have been reviewed in Section 10.03.3.2.60 In contrast, non-directed sp2-C-H functionalization processes are invariably less selective but synthetically more desirable since a directing group is not required. Examples of selective non-directed sp2-C-H functionalizations will be presented, where the regioselective outcome of the reaction is usually more difficult to control. 

Merry-go-round processes involving multiple C-H functionalizations and carbometallations have been described. In the example depicted, a rhodium hydride continues to be formed until steric factors prevail. The 2-norbornene moiety acts as a directing group (Equation (148)).125... 

The above reaction is complementary to a related heterocyclization process, which may proceed by a C-H functionalization of the aryl group (Equation (162)).136... 

Similar intramolecular hydroarylations of alkynes and alkenes, which obviate the need for a halide or triflate group on the aryl ring, are now well established. Sames group screened over 60 potential catalysts and over 200 reaction conditions, and found that Ru(m) complexes and a silver salt were optimal. This process appears to tolerate steric hindrance and halogen substrates on the arene (Equations (175)—(177)). The reaction is thought to involve alkene-Ru coordination and an electrophilic pathway rather than a formal C-H activation of the arene followed by alkene hydrometallation, and advocates the necessary cautious approach to labeling this reaction as a C-H functionalization... 

Group 8 metals, 1, 745 Group 9 metals, 1, 745 chalcogen-chalcogen additions, 10, 755 C-H functionalizations, 10, 123 chloroboration, 9, 166... 

C-H functionalization, 10, 121 C-H intermolecular functionalization, 10, 122 C-H intramolecular functionalization, 10, 130 olefin functionalization, 10, 155 /)3-Carbon atoms, C-H bond functionalization activated alkyl groups intermolecularly, 10, 111 activated alkyl groups intramolecularly, 10, 114 alkanes and alkyl units, 10, 102 Carbon-based ligands, alkali metal chemistry, 2, 3 Carbon-based 77-ligands, in molybdenum carbonyls alkenes, 5, 433 alkynes, 5, 435 allenes, 5, 433... 

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