Superoxides alcohol inversion

The method has been extended to inversion of steroid and prostaglandin alcohols. In some cases it is superior to inversion with potassium superoxide (6, 488-489).2... 

The reactions of alkyl sulfonates with superoxide ion and with nitrite ion directly afford the corresponding inverted alcohols. - Although displacement by superoxide ion has been successfully utilized in prostaglandin chemistry, elimination again takes place to some extent, depending on the structures of the substrates. In the reaction with nitrite ion, ketone and nitroalkane are also formed. The inversion of cyclopentanol derivatives via tosylates has been studied by the use of various methods involving displacement by benzoate, nitrite ion and superoxide ion as well as the diethyl azodicarboxylate (DEAD)-PhsP procedure, where varied amounts of elimination products are invariably formed. ... 

The reaction of primary alkyl bromides or sulfonate esters with potassium superoxide solubilized in benzene gives dialkyl peroxides, ROOR, as the major product. Significant amounts of alcohols and olefins are also formed. If the reaction is carried out in DMSO or DMSO-DMF, primary alcohols are formed very rapidly with inversion of configuration. Catalytic amounts of a crown ether are sufficient, but use of 1-2 eq. leads to a more rapid reaction. Secondary alcohols can be obtained, often in high yield, by this displacement reaction, but elimination predominates with tertiary substrates. This Sn2 reaction has been... 

The first reaction between alkyl halide and superoxide anion in DMSO is a nucleophilic displacement process (Eq. 8.3), since reaction with optically active secondary halides, tosylates, and mesylates leads to alcohols with inversion of configuration at the active center. The small relative rate difference observed between primary and secondary alkyl halides is difficult to reconcile with the usual Sn2 reactivity pattern [6, 9]. Examples of the transformation of alkyl halides into alcohols in DMSO solution are presented in Table 8.2. 

Crown-catalysed substitution by chromate ions provides a direct oxidation route from primary halides to aldehydes via chromate esters (39). Superoxide anion becomes a useful new type of oxygen nucleophile now that potassium superoxide can be solubilized with 18-crown-6 and derivatives. Alkyl halides or sulphonates (RX) may be converted to alcohols or dialkyl peroxides, depending on the exact conditions, through an initial nucleophilic substitution with inversion (Scheme 8). 

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