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Chemistry Forums for Students => Organic Chemistry Forum => Topic started by: zeshkani on October 02, 2006, 04:43:04 PM

Title: Newman Projections
Post by: zeshkani on October 02, 2006, 04:43:04 PM

hi there iam haveing some trouble with this question, iam sure its easy, but i just dont understand it

1. Using newman projection, draw all staggered and eclipsed conformations that result from rotation around the indicated bond in the following molecule.  CH3CH2__CH2CH2CH3 .

if anybody can help, that would be great
thanks
                                             

Title: Re: Newman Projections
Post by: movies on October 02, 2006, 05:30:55 PM

This may help:

http://www.bluffton.edu/~bergerd/Models/newman.html

Title: Re: Newman Projections
Post by: english on October 04, 2006, 11:56:04 PM

This is a rotation about C-2 and C-3 carbons as you have indicated.

Draw your C-2 carbon in front, C-3 in back.

C-2 will have 2 H bonds and 1 CH₃ bond.  C-3 will have 2 H bonds and 1 CH₂CH₃ bond.

Now just rotate the front (or back) continuously at 60° intervals.  This will give you 3 staggered and 3 eclipsed conformations.