Zinc manganese dichloride

See Zinc Manganese dichloride See other metal halides... 

It is used to make oxygen in laboratories. One has to heat a mixture of manganese dioxide and an alkaline chlorate. This reaction, which is known for not being dangerous and often used in lectures, gives rise to anhydrous manganese dichloride which reacts explosively with potassium or zinc. Detonation of the mixture is known to have led to several accidents. 

Anaqueous manganese dichloride reacts explosively with potassium or zinc. 

Zinc gives an explosive reaction with manganese dichloride, whereas with calcium chloride, which was in a galvanised iron container, the detonation is blamed on the overpressure created by the release of hydrogen, which is formed in these conditions. 

Zinc foil reacts explosively when heated with anhydrous manganese dichloride. 

A similar hybrid type of radical/anionic reactions can be effected, when manganese metal, activated by catalytic amounts of lead dichloride and trimethylchlorosi-lane, is employed instead of zinc, which makes the original process synthetically more reliable and attractive by reducing the amounts of reagents (RX and ketone) needed to a 1.5 molar excess over the alkenes (Scheme 6.36) [57]. 

Catalytic transformations circumventing this problem have been realized by protonation of titanium oxygen and carbon bonds in the presence of 2,4,6-collidine hydrochloride and a stoichiometric reducing agent, usually zinc or manganese. The reaction conditions for the reductive opening in the presence of 5 mol% titanocene dichloride are depicted in Scheme 24 [41]. 

---