• Blog Stats

    • 82,806 hits
  • Archives

  • Enter your email address to subscribe to this blog and receive notifications of new posts by email.

    Join 158 other followers

  • Copyright notice

    This blog entry and all other text on this blog is copyrighted, you are free to read it, discuss it with friends, co-workers and anyone else who will pay attention.

    If you want to cite this blog article or quote from it in a not for profit website or blog then please feel free to do so as long as you provide a link back to this blog article.

    If as a school teacher or university teacher you wish to use content from my blog for the education of students then you may do so as long as the teaching materials produced from my blogged writings are not distributed for profit to others. Also at University level I ask that you provide a link to my blog to the students.

    If you want to quote from this blog in an academic paper published in an academic journal then please contact me before you submit your paper to enable us to discuss the matter.

    If you wish to reuse my text in a way where you will be making a profit (however small) please contact me before you do so, and we can discuss the licensing of the content.

    If you want to contact me then please do so by e-mailing me at Chalmers University of Technology, I am quite easy to find there as I am the only person with the surname “foreman” working at Chalmers. An alternative method of contacting me is to leave a comment on a blog article. If you do not know which one to comment on then just pick one at random, please include your email in the comment so I can contact you.

  • Advertisements

What the FAME profile of a bar of soap told me

The other day I converted the carboxylic acid salts in a bar of soap into methyl esters using a Fisher ester synthesis. I then used GCMS to examine the mixture.

I found that the soap contained C12, C14, C16 and C18 carboxylic acids. This made me think.

I know  that living things normally only make even carbon carboxylic acids as their fatty acids, but I started to think of some of the alternatives.

1. Could SHOP (Shell Higher Olefins Process) be used to make oligomers of ethylene which could then be converted by a modified hydroformylation into carboxylic acids ?

Answer, no such an industrial synthesis would make odd carbon fatty acids. SHOP will make olefins with even numbers of carbons, the hydroformylation will add a single carbon atom to the chain thus making an odd carbon chain aldehyde.

2. Could SHOP be used to make a mixture of alkenes which could then be converted by Wacker chemistry into aldehydes and then into carboxylic acids.

Answer, no. While the Wacker process makes ethanal (acealdehyde) from ethylene (ethene) the related process published by Jiro Tsuji et. al. forms methyl ketones and not aldehydes. So this method can not be used to make the fatty acids.

3. Maybe is could just be the case that the carboxylic acids were made in a green plant two carbons at a time.

If anyone can think of some alternative method for making the even carbon fatty acids in bulk then please suggest it in the comments.


Go on, Have your say !

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s

%d bloggers like this: