ozonolysis

Usually in DCM/MeOH at -78C.
Why MeOH?
literature said MeOH can keep ozone longer in solution. Actually once I did it without MeOH, big scale, The result is that I can't see the blue color! So MeOH can also serve as an indicator!
If you have another functional group which is also sensitive to ozone, you can use an indicator, sudan III is one.
Triphenylphosphine or dimethyl sulfide can be used to workup the ozonide if you want a ketone.
Zinc dust is also OK.
NaBH4 is used to reduce the ozonide to alcohol. Now MeOH is important because it can dissolve NaBH4.

A good alternative way to cut the double bond is to use PhIO in water. J. Am. Chem. Soc., 129 (10), 2772 -2773, 2007.