Amine reaction with electrophilic olefins

The contribution of increased steric effects to a lower nucleophilicity was mentioned earlier. Russian workers (29, 56) who studied addition and substitution of a large number of amines with electrophilic olefins analyzed the reactions in terms of dual-parameter equations involving polar and steric effects. 

Table IX. Parameters of Equation 4 for Reactions of Amines with Electrophilic Olefins at 25 °C...

Abstract Aldehydes obtained from olefins under hydroformylation conditions can be converted to more complex reaction products in one-pot reaction sequences. These involve heterofunctionalization of aldehydes to form acetals, aminals, imines and enamines, including reduction products of the latter in an overall hydroaminomethylation. Furthermore, numerous conversions of oxo aldehydes with additional C.C-bond formation are conceivable such as aldol reactions, allylations, carbonyl olefinations, ene reactions and electrophilic aromatic substitutions, including Fischer indole syntheses. 

Bis(trifluoromethyl)diazomethane is a reactive, electrophilic compound. It forms adducts with nucleophiles such as amines and phosphines5 and adds to olefins, acetylenes,5 and thiocar-bonyl compounds6 to form heterocycles. It has been used as a source of bis(trifluoromethyl) carbene in reactions with benzene,5 saturated hydrocarbons,7 carbon disulfide,8 and transition metal compounds,8 and it undergoes a unique radical chain reaction with saturated hydrocarbons to form adducts that are hydrazoncs and azines.7... 

Chemically, CS is a moderately reactive electrophile due to the presence of two electron-withdrawing nitrile groups attached to the olefinic bond. The site of reaction with nucleophiles is the olefinic carbon adjacent to the aromatic ring. Reactions are SN2-like, i.e. CS reacts with nucleophiles directly in a bimolecular fashion. CS reacts quite rapidly with water when in solution (half-life 14 min, 25°C, pH 7.4) to give 2-chlorobenzaldehyde and malonitrile. Reactions are much faster with thiols and amines. CS reacts rapidly with glutathione and plasma protein, although the reaction products have not been characterized (Cucinell et al., 1971). 

Moreover, a study has been made on the effect of fluorine substitution in the MBH reaction of various fluorocarbonyl partners with acrolein, methyl vinyl ketone, ethyl acrylate and acrylonitrile. Multifunctionalized fluorinated allyl alcohols were prepared from amine-sensitive aldehydes and olefins by balancing their reactivities. When the olefin is capable of reacting with itself in the presence of an amine e.g. acrolein), the electrophile has to be very reactive as well e.g. fluoral) to obtain a modest to good yield of MBH products. The reaction of a moderately reactive olefin e.g. ethyl acrylate or acrylonitrile) and a very reactive electrophile e.g. fluoral) resulted in self-reaction of the electrophile or very low yield of the allylic alcohol product. 

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