Allylic derivatives nitrogen substitution reactions

Complexes derived from the oxazolinylpyridine ligand Ph-Pybox and [Ir(COD)Cl]2 catalyze allylic substitution reactions of several oxygen and nitrogen nucleophiles... 

The palladium catalysed substitution reaction of allylic systems has also been utilised in the formation of five membered rings. Intramolecular nucleophilic attack of the amide nitrogen atom on the allylpalladium complex formed in the oxidative addition of the allyl acetate moiety on the catalyst led to the formation of the five membered ring (3.63.). In the presence of a copper(II) salt the intermediate pyrroline derivative oxidized to pyrrole.80... 

Perimidine has an acidic NH proton and therefore behaves differently from pyrimidine and quinazoline. The product is a neutral molecule. Like imidazoles, perimidines are best A-alkylated in alkaline media (79) in an inert atmosphere. Alkylation with primary alkyl bromides or iodides can be performed in an alcoholic solution. Dimethyl sulfate is recommended for methylation. Yields drop with secondary halides. A-Substitution reactions are sensitive to steric interference from 2-and 4(9)-substituents 2-alkyl or aryl derivatives can be methylated but not alkylated by benzyl chloride or isopropyl, allyl or phenacyl bromides. 4(9)-Substituted perimidines are preferentially alkylated at the remote nitrogen. 

V.2.1.7 Palladium-Catalyzed Substitution Reactions of Nitrogen and Other Group 15 Atom-Containing Allylic Derivatives... 

Pd-catalyzed reactions of allylic esters such as aUyl acetates, carbonates, and phosphates with soft carbon nucleophiles such as malonate esters are useful for carbon-carbon bond formation (Sects. V.2.1.1-V.2.1.5). hi this section, Pd-catalyzed substitution reactions of nitrogen-containing allylic derivatives such as allylic amines, ammonium salts, tosylim-ides, and nitro compounds are described (Scheme 1). The allylic derivatives of other group 15 atoms have never been used as allyl unit source in Pd-catalyzed alkylation reactions so far. 

The product is a diacyl derivative of an amine. Thus, the lone pair electrons of nitrogen are so effectively delocalized that they cannot displace a halide even from a compound as reactive as allyl chloride. Thus, only a single substitution reaction occurs. 

As shown in Scheme 2.21 Id, starting with N-allyl carbohydrate-nitrones (469), a series of chiral six- (470) and seven-membered(471) TV-heterocycles were synthesized (Scheme 2.227). A very interesting and useful aspect of this cycloaddition is the control of regioselectivity by the substitution at the nitrogen atom. Therefore, it is possible to direct reactions towards the syntheses of preferred six- or seven-membered heterocycles from carbohydrate derivatives (722). 

Pyrrolo[3,2-f]pyridine can be readily substituted with a variety of electrophiles at C-2 or C-3 after protection of the ring nitrogen atom. Derivatives can be synthesized with substituents such as iodo, methyl, trimethyltin, formyl, and allyl groups. The reactions proceed with excellent yields (47-95%) <200583581 >. 

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