Big Chemical Encyclopedia

Chemical substances, components, reactions, process design ...

Articles Figures Tables About

Bromo ketones, reaction with boranes

The reaction is considered to involve formation of the anion of the a-bromo ketone, reaction with the borane. and rearrangement. Use of potassium /-butoxide in /-butanol gave much lower yields. The a-bromo ketones were prepared by the reaction of ketones with cupric bromide in ethyl acetate-chloroform (method of L. C. King and G. K. Ostrum [J. Org., 29,3459(1964)] see 1, 161-162). [Pg.448]

Hydroboration of 1-bromo-l-alkynes with chloro(thexyl)-borane leads to the synthesis of alkynyl ketones in 61-63% yields by the sequence of reactions shown in eq 5. Sequential treatment of alkenylchloro(thexyl)boranes, which are formed by the reaction of chloro(thexyl)borane with alkynes, with lithium chloro-propargylide and aldehydes affords 1,3-enynols or 1,2,4-trienols depending on the reaction conditions. ... [Pg.145]

Dilithium tetrachlorocuprate is recommended as an additive for cross coupling of Grignard compounds with tosylates even allylic and benzylic acetates give good yields . a-Methylene-ketones, -carboxylic acids and -lactones have been prepared via sulfides and sulfoxides. A convenient and general synthesis of acetylene derivatives from boranes via the reaction of iodine with lithium 1-alkynyltriorganoborates has been published ar-Nitrostyrenes can be easily obtained by a Wittig synthesis with formaldehyde in an aqueous medium . A new synthesis of unsym. ketones by reaction of dialkyldiloroboranes with lithium aldimines has recently been published . Metallo aldimines have also served for the synthesis of a variety of other compound classes such as a-hydroxyketones, a-keto acids, nitriles, and for the asym. synthesis of a-amino acids . Polycondensations of malononitriles with benzylic chlorides have been carried out quantitatively under mild conditions in dimethyl sulfoxide with triethylamine as acid acceptor . Carbonyl compounds can react with dibromoacetonitrile to yield a-bromo esters with additional carbon atom . ... [Pg.10]


See other pages where Bromo ketones, reaction with boranes is mentioned: [Pg.16]    [Pg.184]    [Pg.27]   
See also in sourсe #XX -- [ Pg.559 ]




SEARCH



Borane ketones

Borane reactions

Borane, with

Boranes reaction with

Boranes reactions

Bromo ketones

Ketones with borane

Ketones, reaction with boranes

Reaction with borane

Reaction with ketone

With boranes

© 2024 chempedia.info