Alkyl-de-hydrogenation

Two further notes (1) Many transformations can be named using either of two reactants as the substrate. For example, the transformation methylene-de-oxo-bisubstitution above, can also be named ethylidene-de-triphenylphosphoranediyl-bisubstitution. In this book, unless otherwise noted, we will show only those names in which the substrate is considered to undergo the reactions indicated by the titles of the chapters. Thus the name we give to 1-12 (ArH + RCI- ArFt) is alkyl-de-hydrogenation, not aryl-de-chlorination, though the latter name is also perfectly acceptable under the IUPAC system. (2) The IUPAC rules recognize that some transformations are too complex to be easily fitted into the system, so they also include a list of names for some complex transformations, which are IUPAC approved, but nonsystematic (for some examples, see reactions 2-44, 8-36, 9-63). 

Alkylation and Arylation of Aromatic Compounds by Peroxides Alkylation or Alkyl-de-hydrogenation... 

Hydrogen as Leaving Group A. Substitution by Haiogen 14-1 Halogenation at an Alkyl Carbon Halogenation or Halo-de-hydrogenation... 

Amidation and Amination at an Alkyl Carbon Acylamino-de-hydrogenation... 

Hydrosilylations of fluorine-containing alkenes are free radical reactions initiated by UV light or organic peroxides The direction of addition is the same as with fluonnated alkyl halides However, the reaction between hydrosilanes and fluorine-containing olefins catalyzed by platinum group metal complexes may result in bidirectional addition and/or formation of a vinylic silane, the latter by de hydrogenative silylation[/] The natures of both the silane and the catalyst affect the outcome of the reaction[7] A random selection of some typical new reactions of silanes are shown in Table 1 [1, 2, 3 4]... 

The major products were found to be 1-phenyloctane, 1-phenylheptane, and the homo-metathesis of n-octane, along with other, linear alkanes. TONs obtained from the olefin metathesis and (de)hydrogenation transfer were 31 and 50, respectively. This scope of this reaction was also extended to include branched alkanes and alkyl silanes with lower yields (6-25%). 

Critical evaluation of the nature of alkyl residues stabilized at C(4a) and/or N(5) allows one to conclude that nucleophilic residues prefer C(4a), while electrophilic ones prefer N(5) (98). Hence, it has been proposed to consider the following reaction sequence for flavin-dependent (de)hydrogenation ... 

Liquid-Ph se Processes. Prior to 1980, commercial hquid-phase processes were based primarily on an AIQ. catalyst. AIQ. systems have been developed since the 1930s by a number of companies, including Dow, BASF, Shell Chemical, Monsanto, SociStH Chimique des Charboimages, and Union Carbide—Badger. These processes generally involve ethyl chloride or occasionally hydrogen chloride as a catalyst promoter. Recycled alkylated ben2enes are combined with the AIQ. and ethyl chloride to form a separate catalyst—complex phase that is heavier than the hydrocarbon phase and can be separated and recycled. 

Methyldihydrostrychnidinium-A acetate is produced in much small amount in the hydrogenation ( internal alkylation) reaction and w isolated as the iodide, m.p. 345-350°, and converted to the chloric which on treatment with sodium methoxide gave methoxymethyltetr hydrostrychnidine (c in the above list) with some des-base-D, and < thermal decomposition yielded dihydrostrychnidine-A. These and oth reactions of des-base-D are regarded as best accounted for by formu (XVIII). ... 

For dirnethyldesweostrychnidine the Achmatowicz formula has been slightly modified to (XIX) by Holmes and Robinson. The third substance, dimethyWesstrychnidine-D yields both a dihydro- and a tetrahydro-derivative and, unlike des-base-D, from which it is derived, does not undergo internal alkylation when subjected to the hydrogenation process in acid solution it is represented by (XX). 

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