User talk:Inouttennis2314

Hydroboration–Oxidation
Thanks for your interest in the hydroboration–oxidation reaction article. I undid your edit to it, however, because you stated that the results are always "enantiomers". That's not true...reaction of cyclohexene gives cyclohexanol, which is not chiral, and reaction of compounds containing an existing stereocenter retain that one's same chirality even if the stereochemistry set by the BH3/H2O2 can go either way.. DMacks (talk) 21:57, 23 October 2012 (UTC)

Good point, thank you for reminding me of such. The main reason i took issue with the sentence was the application of the term 'cis'. I do not think the terms 'cis' or 'trans' should be applied to anything but alkenes with identical pairs of substituents. Perhaps, it should be expanded to say that if a two new asymmetric centers are created then there will be a pair of enantiomer products? Inouttennis2314 (talk) 03:02, 24 October 2012 (UTC)
 * "Syn" is a more proper term than "cis" for the geometry of the reaction...the H and OH occur in the "same direction" compared to the original alkene regardless of what else might be attached to the alkene or to the geometric details/terminology for the product structure. The article does use that exact description. I don't completely understand your comment about "identical pairs of substituents", but cis/trans definitely is proper terminology for cyclic compounds as well as for alkenes in general (same origin: the bonds are not free to rotate all the way around) and is even used in the title of Ref #2 in the article in that context. In all cases where there is a geometric/stereochemical cis/trans aspect to the product, the H and OH are cis assuming there are not additional shape changes. The article would really benefit from an image of this sort of detail, since all the current diagrams only cover the intermediates and anti-Markovnikov aspect, not the stereochemistry.
 * Assuming there are just simple stereocenters formed (rather than these additional ring effects), the relationship between the two expected stereoismers (H/OH syn on one face vs the other of the alkene) is also not necessarily enantiomeric (2Z,4R)-3,4-dimethyl-2-hexene gives a mixture of (2R,3R,4R)- and (2S,3S,4R)-2-hydroxy-3,4-dimethylhexane. They are exactly inverted at the sites of the H-B reaction, but the chemicals themselves are diastereomers. DMacks (talk) 07:52, 25 October 2012 (UTC)