C-Alkyl migration

Rearrangement of an enamine to a Sehiff s base through N- to C-alkyl migration was reported 729). These authors also found that enamines, rather than aminals, were formed from butyraldehyde and seeondary amines (730). Chloramines and aeetylenes reacted to give chloroenamine intermediates, which hydrolyzed on work-up of the reactions (731). 

Although both boronates and alanates react with allylic bromides, aldehydes and C02 to afford allenic products in satisfactory yield, the alanates are more efficient in additions to ketones (Table 9.14). Boronate reagents do not require a B-C alkyl migration for their preparation. Thus the starting acetylene possesses the structural elements of the product. Additionally, the issue of dummy ligands is irrelevant. 

An indirect way to effect alkylation at an ip -carbanionic center is by reaction with a trialkylborane (Scheme 4)." Decomposition of the intermediate borate results in overall alkylation of the original Grig-nard species by B C alkyl migration one drawback is that two of the alkyl groups are wasted and hence applications would probably be somewhat limited. 

Without additional reagents Thermal C-alkyl migration... 

C-alkyl migration 21, 923 replacement of halogen by hydrogen 21, 965 —, dehaiogenative 21, 28 —, preferential 2, 767 Aroxyls... 

Protonation of Li-alkynyltrialkylborates with acid can be directed to achieve a double B- -C-alkyl migration. - E w-Butyllithium in hexane added dropwise at... 

C-alkyl migration 28,708 Gattermann-Kodi-type isoquinoline synthesis 28, 743 gem (germinate) (s. a. 1,1-) s. gem-Dimethyl effect, gem-Divinyl compds., gem-Hydrogenolysis Geoisomerization s. under Ethylene derivs. 

Aluminum chloride hydrogen chloride Synthesis of indan-l-one-3-carboxylic acids with C-alkyl migration... 

A novel Michael addition with B C-alkyl migration has been reported 3 Ketones with acid-labile functional groups can be synthesized from aldehydes via new a-siloxyphosphonates. ... 

Alkylmagnesium halides s. under Magnesium Alkylmercapto... s. Alkylthio... Alkyl migration -, S-alkyl from O-alkyl 32, 590 -, Se-alkyl from O-alkyl 32, 590 B- -C-Alkyl migration, double... 

Hydrogen fluoride boron fluoride C-Alkyl migration... 

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