Hydroboration of alkynes using BH3 to give aldehydes

by James

Description: When alkynes are treated with BH3 and subsequently treated with H2O2, they are converted into aldehydes.
Content available for Reactionguide members only. Not a member? Get access for about 30 cents / day!

{ 5 comments… read them below or add one }

nuha November 21, 2011 at 7:03 pm

This is SOO helpful! Thank you. I’m only in OChem 1 and often they tell us not to worry about knowing these longer mechanisms, but just seeing them and having them explained once or twice helps me understand everything else!
Thanks again for breaking it down into bite-sized pieces!


Rosemary May 17, 2013 at 11:38 pm

” Then comes the weird step! The carbon-boron bond breaks, and the examples from this bond migrate to the oxygen”
Do you mean to say examples here or do you mean something else (electrons?)


james May 23, 2013 at 4:46 pm

Oops. Yes, thank you!


Payam Zohdi November 27, 2015 at 10:44 pm

Can example 3 also form two products equally like example 4 because the double bond being on the adjacent carbon would still result it being on a carbon that is equally substituted correct? I am having a hard time seeing the difference between example 4 and 3 both look like the two options are both on secondary carbons


James November 28, 2015 at 8:40 am

In example 3, no matter what side of the alkyne is added to, the product is still 2-butanone. remember that there is no such thing as 3-butanone since we always number the molecule in such a way as to keep the number the lowest.


Leave a Comment