Go Back   Science Forums Biology Forum Molecular Biology Forum Physics Chemistry Forum > General Science Forums > Chemistry Forum > Organic Chemistry Forum
Register Search Today's Posts Mark Forums Read

Organic Chemistry Forum Organic Chemistry Forum


stability of carbokation(?) as in SN1 Reactions

stability of carbokation(?) as in SN1 Reactions - Organic Chemistry Forum

stability of carbokation(?) as in SN1 Reactions - Organic Chemistry Forum


Reply
 
LinkBack Thread Tools Display Modes
  #1  
Old 01-12-2004, 05:00 PM
LOUIS
Guest
 
Posts: n/a
Default stability of carbokation(?) as in SN1 Reactions



C6H5-CH2Br is an activated halide (kind of allylic position) and thus despite it is a R-X compound it displays reactivities between
secundary and tertiary halides (R2CHBr and R3CBr) .But reactivity isn't stability and if (CH3)3C(+) is stabilised by the three CH3 (I+
effect), in the benzylic position all the aromatic ring participates to the stability and the resonance will help a bit.
Thus so far t-butyl bromide > or = to Ar-CH2-Br on reactivity and stability.

The introduction of a -C#N will make the benzilic position more electronegative (more acidic) and thus renders the formation of a
carbocation less easy...it starts to prefer to allow H(+) ore Br(+) to leave a carbanion.
Actually the more aromatic ring or electron withdrawing groups (-CO2R, -NO2, -C#N, -CO-R, ...) on a Carbon the more it favors radicalar
stabilisation/splitting...radicalar splitting means the carbon keeps one electron.
See (Ar)3C-C(Ar)3, (Ar)3C-Br, (N#C-)3C-C(-C#N)3, Br-C(NO2)3.

Thus to my feeling:
3>or =2 >1

Ph Z
Johannes Babach wrote:





--
Paul J. Franklin(moderator - sci.chem.organic.synthesis)
[Only registered users see links. ]
Georgia State University <[Only registered users see links. ].edu>
Atlanta, GA
Reply With Quote
Reply

Tags
carbokation , reactions , sn1 , stability


Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
The products of the light dependent reactions in photosynthesis? surferasianboi Biology Forum 0 07-07-2009 11:18 PM
Magnetic Bead Cleanup of BigDye Terminator Reactions MICHAEL L SULLIVAN Protocols and Methods Forum 0 04-22-2004 01:42 PM
stability of carbokation(?) as in SN1 Reactions GeneralChemistryTutor Organic Chemistry Forum 0 01-20-2004 08:41 PM
stability of carbokation(?) as in SN1 Reactions Johannes Babach Chemistry Forum 5 01-12-2004 09:15 PM
stability of carbokation(?) as in SN1 Reactions Johannes Babach Organic Chemistry Forum 0 01-05-2004 07:27 PM


All times are GMT. The time now is 09:13 AM.


Powered by vBulletin® Version 3.8.4
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Copyright 2005 - 2012 Molecular Station | All Rights Reserved
Page generated in 0.10977 seconds with 16 queries