Boron trihalide adducts properties

II. Preparation, Detection, and Properties of Mixed Boron Trihalide Adducts 149... 

The near-random redistribution of fluorine and chlorine in oxygen-donor boron trihalide adducts (27, 29) might be rationalized using this principle since oxygen is between fluorine and chlorine on the hard-soft scale (140), and there is less discontinuity of ligands in terms of hard-soft properties. However, amine adducts of BHF2 do tend to disproportionate to give the BF3 and BH3 adducts (130). 

Pyridazine forms a stable adduct with iodine, with semiconductor properties. " Similar complexes were prepared from iodine mono-ehloride, bromine, and nickel(II) ethyl xanthate. Complexes of pyrida-zines with iron carbonyls and with iron carbonyls and triphenylphosphine have been prepared and investigated. " Complexes of pyridazines with boron trihalides, silver salts, mercury(I) salts, iridium salts, " ruthenium salts, and chromium carbonyls are re-... 

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