would it be the cis one??? because the Br2 adds anti-additions which can do both faces in cis but in trans it would just produce the same molecule which would not be racemic...
would it be the cis one??? because the Br2 adds anti-additions which can do both faces in cis but in trans it would just produce the same molecule which would not be racemic...
Above is incorrect. Cis------->Anti Pathway---> will yield a racemic mix of enantiomers. Trans--->Anti Pathway----> will yield a meso compound, depending on the symmetry of the starting material.
Above is incorrect. Cis------->Anti Pathway---> will yield a racemic mix of enantiomers. Trans--->Anti Pathway----> will yield a meso compound, depending on the symmetry of the starting material.
I am 100% positive that a cis alkene with an anti-addition (which is what the Br- that attacks the bromonium ion or bromine bridge does). This is how you check it. Put the methly groups both as wedges and the H's both as dashed or other way around in the alkene. When you attack with Br2 you will end up getting wedge up methyl, dashed hydrogen and bromine up on one side. On the other carbon you get wedge up methly, dashed hydrogen and bromine down. Now you have to take one of these and rotate it 180 degrees so the bromines are either both up or both down. When you do this one of the methly groups will switch to dashed and the Hydrogen will switch to wedged. THis is one of two enantiomers since the bridge can form up or down. If you started trans and did the rotation everything would lie in the same planes-hence the meso compound.
If you know how to insert a scanned document let me know. I will go through the rxn scheme.
