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Chemistry Forums for Students => Organic Chemistry Forum => Topic started by: faust on October 23, 2005, 04:14:21 AM

Title: which will be the less polar : allyl amine of tosylated allyl amine?
Post by: faust on October 23, 2005, 04:14:21 AM

Hello,

I know it's maybe a stupid question... but.. on a TLC plate, which will be the less polar : allyl amine of tosylated allyl amine?

Thanks

Title: Re:which will be the less polar : allyl amine of tosylated allyl amine?
Post by: movies on October 23, 2005, 04:40:26 PM

What would you expect the trend to be as you progressed from a primary amine to a secondary and then a tertiary amine?  Think in terms of the availibility of hydrogens and lone pairs for hydrogen bonding or other polar interactions.

Title: Re:which will be the less polar : allyl amine of tosylated allyl amine?
Post by: faust on October 26, 2005, 01:09:04 AM

I tought that the tertiary amine will be the more polar simple because It's the more nucleophilic indeed it have 3 donnating groups (3 alkyls)

But the NMR says the opposite :)

the secondary amine is the more polar...

Title: Re:which will be the less polar : allyl amine of tosylated allyl amine?
Post by: movies on October 26, 2005, 01:57:59 PM

True, a tertiary amine will have a more electron rich nitrogen, however you have to also account for the difference in how accessible that nitrogen is.

Also, a tosyl group is an electron withdrawing group through resonance.