Hydrocarbyl substituents

Carbonyl compounds will be taken in this chapter to mean any organic compound that contains at least one carbon-oxygen double bond where we limit the substitution to only saturated aliphatic, saturated alicyclic and aryl hydrocarbyl groups. Carbonyl compounds with a variety of unsaturated substituents have earlier been discussed within the context of enones4. Non-hydrocarbyl substituents, X , may be directly attached to the carbonyl and elsewhere in the molecule. The first type of species, RCOX, is alternatively identified as acyl derivatives such as carboxylic acids and their esters, halides and amides and have already been discussed in a recent Patai thermochemistry... 

Were we to relax our restriction to consider solely hydrocarbyl substituents and accept both benzenoid and non-benzenoid aromatic imines, we would find other relevant compounds. For example, there is ALf-butyl-p-nitrobenzaldi mi ne with a gas-phase enthalpy of formation of 49.4 3.6 kJmol-1 from W. E. Acree, Jr., J. J. Kirchner, S. A. Tucker, G. Pilcher and M. D. M. C. R. Ribeiro da Silva, J. Chem. Thermodyn., 21, 443 (1989) and A-methyl-7-(methylamino)-troponimine (misnamed in our principal archive, Reference 16) with a gas-phase enthalpy of formation of 211.2 4.2 kJmol-1. Another relevant species is ammonium murexide with its 100-year-old enthalpy of formation of — 1212 kJ mol-1 as chronicled by Domalski. These three compounds are interesting, but it is precisely the non-hydrocarbyl part of these species that confounds simple comparison with other interesting species in this chapter. 

The pentamethyl cyclopentadiene lanthanide complexes containing hydrocarbyl substituents have been studied extensively for their applications in homogeneous catalysis and C-H activation. The well-known catalyst of the Ziegler-Nutta type Cp2LnMe(Et20) is typical of the large number of compounds [155] that have been studied. Solvent-free electrophilic alkyl derivatives serve as precursors of the majority of the compounds which have been studied. 

R = hydrocarbyl substituents of fused ring systems (indenyl, fluorenyl and substituted derivatives). 

For an efficient, directed synthesis of rrans-tetiahydro-P-carbolines such as (24), hydrocarbyl (e.g. benzyl) substituents at the amino function and at the pyrrole nitrogen of the tryptophan ester, as in (23), are favored (Scheme 13). Under kinetically controlled nonacidic conditions, small amounts of the... 

Hydrazines - Hydrazine (diazane), H NNH, and its hydrocarbyl derivatives. When one or more substituents are acyl groups, the compound is a hydrazide. [5]... 

The effect of phenyl and pentafluorophenyl substituents on the inter-and intramolecular structures of crystalline ferrocene derivatives (5-7, Fig. 5) was investigated by Hughes and coworkers. In the crystal structure of the homoleptic purely hydrocarbyl ferrocene... 

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