1.2- Diiodides special

Contact with RmMX (R is methyl, ethyl M is aluminium, zinc X is bromide, iodide) causes ignition. Diethylaluminium bromide, dimethylaluminium bromide, ethylaluminium bromide iodide, methylzinc iodide and methylaluminium diiodide are claimed as specially effective. 

All the aforementioned evidence for cluster formation is indirect. In this laboratory we have recently observed a special type of cluster formation that supports the notion that such clusters may exist. Rey and McConnell41 have described the preparation of two spin labels, N,N -dipalmitoyl-N,N -bis-(l-oxyl-2,2,6,6-tetramethylpiperidin-4-yl)-l, 10-diaminodecane (VII) and N,N -dimethyl-N,N -dihexadecyl-N,N -bis-(l-oxyl-2,2,6,6-tetramethylpiperidin-4-yl)-1,10-diammoniumdecane diiodide (VIII). 

The literature on PE spectra of halogen compounds including those of silicon has been covered up to 1983 in a special review within this series96 the few, most recently investigated organosilicon halides are listed with their first vertical ionization energies in Table 7. The example selected is silicon diiodide or diiodosilylene containing 90% iodine and twofold coordinated silicon, which shall conclude this review as a radical cation with dominant relativistic properties. 

The release of ring strain in epoxides is probably responsible for the high reactivity of these special ethers. HI opens epoxides under mild conditions stereospecifically to iodohydrins (Scheme 26). The mechanism is similar to the reaction of bromide with epoxides (see Section 1.7.3.3). It should be noted, however, that reduction of epoxides to alkenes may occur if vicinal diiodides are intermediately formed, which can lose I2 under the reaction conditions. With the combination of acyl chloride and Nal unstable diiodides are avoided and 2-iodoethyl esters are formed from oxiranes (Scheme 27). ° ... 

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