Heteroatom nucleophile

Conjugate Addition of Heteroatom Nucleophiles and Subsequent Nef Reaction... 

Aziridines bearing heteroatom substituents are best prepared through treatment of the corresponding azirines with heteroatom nucleophiles. Thus, azirine carbox-ylates (in this case prepared by thermal decomposition of the corresponding vinyl... 

Addition of heteroatomic nucleophiles to divinyl sulphoxides gives mono and bi-functionalized products as well as compounds resulting from their cyclization. For... 

ARYLATION OF HARD HETEROATOMIC NUCLEOPHILES USING BROMOARENES SUBSTRATES AND Cu, Ni, Pd-CATALYSTS... 

The arylation of different hard heteroatomic nucleophiles with arylbromides has been investigated using Pd, Ni or Cu-catalysts. 

The fundamental and pratical importance of arylation, particularly the arylation of heteroatomic nucleophiles, was several times emphasized in the last few years (refs. 1, 2) (eqn. 1). 

The Michael addition of heteroatom nucleophiles to nitroalkenes (Section 4.1.1) followed by denitration provides a useful method for the preparation of various natural products. 

Cationic Fp (olefin) complexes [Fp = f/5-C5H5Fe(CO)2] undergo regio-specific addition of heteroatomic nucleophiles.32 Subsequent ligand transfer (carbonyl insertion) occurs with retention of configuration at the migrating center (R—Fe—CO -> RCOFe).33 A combination of these processes has provided a novel stereospecific azetidinone synthesis which can also be applied to condensed systems.34... 

Ring-opening with heteroatomic nucleophiles is certainly among the most thoroughly studied behavior of epoxides, and this reaction continues to be a versatile workhorse of synthetic utility. This is exemplified in the recent literature by the examples of the p-cyclodextrin-catalyzed aminolysis of simple epoxides by aniline derivatives (i.e., 53 - 54) <00SL339> and the synthesis of oxa-azacrown ethers through the treatment of Ws-epoxides 55 with diamines 56. Yields in the latter synthesis are sensitive to the size of the macrocycle and substitution on the bis-epoxide <00TL1019>. 

A review of the reaction of nitroalkanes RNO2 with carbon and heteroatom nucleophiles X to yield RX has appeared438. The nucleophilic displacement of a nitro group in benzylic and tertiary nitroalkanes by a thiophenyl group is exemplified in equation 130439. 

The radical cation can alternatively react with a heteroatom nucleophile (Scheme lb) and after deprotonation lead to a radical bound to the nucleophile. This radical can be further oxidized to... 

The regio- and diastereoselective rhodium-catalyzed sequential process, involving allylic alkylation of a stabilized carbon or heteroatom nucleophile 51, followed by a PK reaction, utilizing a single catalyst was also described (Scheme 11.14). Alkylation of an allylic carbonate 53 was accomplished in a regioselective manner at 30 °C using a j-acidic rhodium(I) catalyst under 1 atm CO. The resulting product 54 was then subjected in situ to an elevated reaction temperature to facilitate the PK transformation. 

Pathway 2 of Scheme 9 corresponds to one of the most interesting developments in the Beckmann rearrangement chemistry. By trapping of the electrophilic intermediate with a nucleophile (Nu ) other than water, an imine derivative 227 is produced that may be used for further transformations. Carbon or heteroatom nucleophiles have been used to trap the nitrilium intermediate. Reducing agents promote the amine formation. More than one nucleophile may be added (for example, two different Grignard reagents can be introduced at the electrophilic carbon atom). Some of the most used transformations are condensed in Scheme 11. 

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