Anti-markovnikov bromination

[wantVCUdental]

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So i know hydroboration gives anti-M. product
and HBR with ROOR gives anti-M

But for some strange reason i came across somewhere that said any radical bromination gives anti-M...
Is that wrong?
I thought that besides the ROOR HBr, all radical bromination (Br2+hv, HBR+hv) give Markovnikov products right?

Thanks

 

[americanpierg]

So i know hydroboration gives anti-M. product
and HBR with ROOR gives anti-M

But for some strange reason i came across somewhere that said any radical bromination gives anti-M...
Is that wrong?
I thought that besides the ROOR HBr, all radical bromination (Br2+hv, HBR+hv) give Markovnikov products right?

Thanks

If you want to REALLy understand it, it gets more complicated than that, but if you just want to memorize the simple rules, there's just a few. NBS plus H2O gives markovnikov with OH on more substituted and Br on less, NBS with radical initiater like CCL4 puts the Br on the more substituted. NBS with benzyl group always puts Br on the benzyl carbon. Peroxides initiates radicals and adds anti across double bonds. Radical bromination gives anti. Radical chlorination gives normal. Bromination with hv gives normal. Chlorination with hv depends on the different number of hydrogens present, but tertiary is still better than secondary and better than primary, I don't remmeber the ratio but I think it was 5:2:1 or somewhere around there. Cl2/hv with isopropyl chloride puts the Cl on the one of the outer carbons, Cl2/hv with butane puts the Cl on one of the two inner carbons. Cl2/hv with a double bond yields markovnikov