SRN1 reaction iodide

Abstraction of a hydrogen atom from the solvent HS [Eq. (66)] makes it desirable to run the reaction in a solvent that is a poor hydrogen-atom donor liquid ammonia is a preferred solvent. Inorganic salts, such as potassium iodide or bromide, may be employed as supporting electrolyte in the SRN1 reaction in NH3. 

Polyfunctional fluoronitro alcohols are provided by die SRN1 reaction of a perfluoroalkyl iodide or alkylene duodides with the anhydrous lithium salt of 2-nitropropane-l,3-diol acetonide. Hydrolysis of the resulting perfluoroalkyl-... 

SRN1 reactions are, in general, eased up sterically. This feature is employed for synthetic purposes. For instance, the cyanoacetate substituent was inserted in the sterically shielded position of a benzene ring (Suzuki et al. 1983) (Scheme 8-14). The reaction proceeds in hexamethylphosphorotriamide. Photoirradiation results in the formation of undesirable by-products, but initiation with cuprous iodide leads to the target substance, at more than 60% yield. 

In what has become a classic example of an SRN1 reaction, the 2-propylnitronate anion undergoes efficient perfluoroalkylation in its reaction with perfluoroalkyl iodides [302] ... 

A large number of radical reactions proceed by redox mechanisms. These all require electron transfer (ET), often termed single electron transfer (SET), between two species and electrochemical methods are very useful to determine details of the reactions (see Chapter 6). We shall consider two examples here - reduction with samarium di-iodide (Sml2) and SRN1 (substitution, radical-nucleophilic, unimolecular) reactions. The SET steps can proceed by inner-sphere or outer-sphere mechanisms as defined in Marcus theory [19,20]. 

Perfluoroalkyl iodides are well-known for their ability to act as substrates in SRN1 substitution reactions [288]. 

Baumgartner, M.T., Pierini, A.B. and Rossi, R.A. (1999) Reactions of 2-and 3-acetyl-l-methylpyrrole enolate ions with iodoarenes and neopentyl iodides by the SRn1 mechanism. Journal of Organic Chemistry, 64, 6487-6489. 

An arylation reaction of potassium thioamide enethiolates was achieved in good yield by treatment with aryl iodides in the presence of FeBr2 or with photochemical irradiation, perhaps through an SRN1 mechanism [122]. 

In a study of SRN1 photoreactions of halothiophenes with phenylthiolates anions, phenylthiothiophene radical anions are formed and the yield of the expected phenylthiothiophene product is limited by the bond rupture in this intermediate the thiophenylthiolate anion is formed and detected as thiomethyl ether after quenching of the reaction by methyl iodide. By adding benzonitrile as an extra electron acceptor, the bond rupture may be controlled and the selectivity of the reaction has been improved in favour of the thiophenyl ether but at the expense of the overall reaction rate [118]. 

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