Sciencemadness Discussion Board

sodium borohydride to sodium triacetoxyborohydride

uchiacon - 18-7-2011 at 18:21

Hey guys,

I'm interested in making a bit of sodium triacetoxyborohydride for future reductive aminations (just got a 1st yr uni organic chem book), and I was just wondering how I could go about this? I saw something about dissolving it in ethyl acetate and adding a few moles of glacial acetic, but I did not find anything more, as the synthesis was incomplete. Google hasn't turned up anything else.
I'm not sure if this is feasible, but any suggestions would be great.

I've just gotten back into organic chemistry, which I almost dropped a year ago. I was doing pyrotechnics and energetic materials, but I decided to stop for want of expensive safety equipment. Now that I'm doing more complex chemistry in high school, I know I should definitely take this as part of my career.

cheers

tmb - 19-7-2011 at 03:06

Make it in-situ. Here is a review:


Attachment: NaBH4 in Carboxylic Acid Media.pdf (434kB)
This file has been downloaded 1302 times


jon - 19-7-2011 at 10:17

ethylacetate is a great solvent for stab

uchiacon - 19-7-2011 at 18:51

hm, I meant triacetoxyborohydride, this looks like it's for acyloxyborohydrides... was there a bit of a mix up here? triacetoxyborohydride is only mentioned once in the whole document.

tmb - 19-7-2011 at 22:57

It is mentioned many times. If you must isolate it, here is how:

NaBH4 (0.1 mol.) was added portionwise to a solution of acetic acid (0.33 mol.) in dry benzene (1 l.), the temperature being kept at 20C. After hydrogen evolution, the precipitate was rapidly collected by suction, washed with diethyl ether, and dried under vacuum.

[Edited on 20-7-2011 by tmb]

Nicodem - 20-7-2011 at 12:29

Quote: Originally posted by uchiacon  
I'm interested in making a bit of sodium triacetoxyborohydride for future reductive aminations (just got a 1st yr uni organic chem book), and I was just wondering how I could go about this?

You could go about this by UTFSE. The most basic skill of every good researcher is the use of TFSE.

PS: Open referenceless threads only in the Beginnings section, where this one is being moved.