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Electron-deficient reagents, activation

However, intermolecular C-F activation, as noted for some of the electron deficient reagents above, would be most important for catalytic or synthetic applications. [Pg.395]

Acrylamide, C H NO, is an interesting difiinctional monomer containing a reactive electron-deficient double bond and an amide group, and it undergoes reactions typical of those two functionalities. It exhibits both weak acidic and basic properties. The electron withdrawing carboxamide group activates the double bond, which consequendy reacts readily with nucleophilic reagents, eg, by addition. [Pg.133]

P-Amino carbonyl compounds containing an a-atkyUdene group are densely functionalized materials, which are widely applied in the synthesis of medicinal reagents and natural products [265]. These products are usually prepared through the classic aza-Morita-Baylis-Hillman reaction [176, 177] of activated imines and electron-deficient alkenes catalyzed by tertiary amines or phosphines. Chen and co-workers, in 2008, identified bis-thiourea 106 as a suitable catalyst for the... [Pg.250]

Electron-deficient alkenes generally require the use of some other epoxidation procedure, owing to their low reactivity under electrophilic addition conditions. Within this categoiy, o,P-unsaturated ketones tend to be the substrates of interest, and basic oxygen transfer reagents are fiequently encountered, such as HjOj/NaOH, t-BuOOH/NaOH, and NaOCl. Much activity has centered around the modification of these traditional conditions to accommodate asymmetric induction. In this regard, variously substituted Cinchona alkaloids (e.g., 39 - 41) have received a fair amount of attention over the past year. [Pg.62]

Pyridylzinc bromide, a commercially available reagent, was used in the synthesis of a series of bipyridyl derivatives (7.20.). Activated coupling partners, such as 2-chloro-4-cyanopyridine, reacted readily at room temperature in the presence of a palladium based catalyst, while less electron deficient halopyridines were coupled at elevated temperatures.27 The same approach was also extended to the preparation of other heterobiaryls.28... [Pg.146]


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Activation electronic

Activator deficiency

Electron activation

Electron deficiency

Electron-deficient reagents

Electrons active

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