Halogen and interhalogen adducts of substituted amido-ions

Abstract

The reaction between N-dimethylchloramine and iodomethane - which yields the species (CH(_3))(_4)N(^+)(CH(_3))(_2)N(IC1)(_2)(^-) - has been investigated with a view to elucidating possible mechanisms, and a number of analagoua and related compounds have been prepared. Variation of initial molar ratios gives rise to different products and ratios of products. A large excess of N-dimethyl chloramine yields a mixture of (CH(_3))(_3)N.IC1 and (CH(_3))(_4)N(^+)(CH(_3))(_2)N(IC1)(_2)(^-) (1:1.55) whereas a one hundredfold excess of iodomethane yields iodine only. With nearly equal of starting materials, (CH(_3))(_4)N(^+)I(^-) is formed. These results suggest a number of competing reactions which became more or less favourable depending on initial reactant concentrations. A proposed mechanism for the reaction leading to the formation of(CH(_3))(_4)N(^+)(CH(_3))(_2)N(IC1)(_2)(^-) has been suggested: (i) (CH(_3))(_2)NC1 + CH(_3)I → (CH(_3))(_3)NC1I (ii) (CH(_3))(_3)NC1I → (CH(_3))(_3)N + IC1 (iii) CH(_3))(_3)N + (CH(_3))(_4)N(^+) I(^-) (iv) (CH(_3))(_2)NC1 + IC1 → (CH(_3))(_2) – Cl →IC1 (v) (CH(_3))(_2) – Cl → IC1 + (CH(_3))(_4)N(^+)I^-) → (CH(_3))(_4)N(^+) (CH(_3))(_2)N(IC1)(_2)(^-) The adduct (CH(_3))(_2)NC1.IC1 is a proposed intermediate, and this substance has been prepared, together with two other previously unknown related compounds (CH(_3))(_2)NC1.IBr and (CH(_3))(_2)NC1.Br(_2). The analogous N-dibenzylchloramine compound (C(_6)H(_5)CH(_2))(_2)NC1.IC1 has also been prepared. Various adducts of N-halami es have been reacted with arge cation halides. he reaction between (CH(_3)0(_2)NC1.IC1 and (CH(_3))(_4)N(^+)I(^-) yields (CH(_3))(_4)N(^+) (CH(_3))(_2)N (IC1)(_2)(^-) , and analogous reactions have produced the now compounds Cs(^+)(CH(_3))N(IC1)(_2)(^-), (C(_6)H(_5))(-2)I(^+)(CH(_3))(_2)N(IC1)(_2)(^-). Attempts to synthesise these and related compounds from N-halamine adducts and large cation tri-iodides have yielded the novel T1(^+) (CH(_3))(_2)N(IC1)(_2)(^-) besides providing a faster route to (CH(_3)(_4)N(^+)(CH(_3))(_2)N(IC1)(_2)(^-) and (CH(_3))(_4)N(^+)(CH(_3))(_2)NI(_4)(^=). A number of halide insertion reactions have been tried and have been shown to produce simple polyhalides or polyhalide mixtures in the majority of cases. Reaction of (CH(_3))(_2)NC1.J(_)2) with (CH(_3))(_4)N(^+)Br(^-) yielded the new substance (CH(_3)(_4)N(^+)(CH(_3))(_2)NIBrCl(_2)(^-), while with (CH(_3))(_4)N(^+)I(^I), the similarly novel (CH(_3)(_4)N(^+)(CH(_3)(_2)NI(_3)Cl(^-) is formed. Reaction of N-dimethyliodamine with iodomethane gives excellent yields of (CH(_3))(_4)N(^+)(CH(_3))(_2)NI(_4)(^-), but various attempts to alkylate N-halamines with allyl iodide failed. Benzyl iodide, on the other hand, produced complex mixtures or simple polyhalides, one such being (CH(_6)H(_5)CH(_2))(_2) (CH(_3))(_2)N(^+)I(_3)(^-) which does not appear to have been previously reported.