Determining R and S Configurations On Fischer Projections From time to time you may be asked to determine R/S on a Fischer projection. So how do you do that? The Fischer projection is an early solution to the problem of drawing 3-dimensional molecules on a 2-dimensional page. Think of a … [Read more...]
Putting the Newman into ACTION
This is a long, graphics intensive post. You probably don't need to read it all now, but chances are, you'll REALLY need to know the skill I describe here soon. Because it's an extremely common question found on The First Midterm. What this post teaches you how to do is to calculate the energies … [Read more...]
Newman Projections
Imagine you have a clock. Not a digital clock. One of those old fashioned clocks with two hands. Let's try something. Make the clock show high noon, so that both hands are pointing at 12. Now pin down down the hour hand so it can't move. (Or if you want, pin down the minute hand. Either one, … [Read more...]
Conformations
You've likely learned by now that you can rotate single bonds ("sigma bonds") but you can't rotate multiple bonds (Pi bonds). Now we can start talking about some of the consequences of this. A molecule with single bonds - an alkane, let's say - has a certain amount of freedom in how its bonds … [Read more...]
Enantiomers vs Diastereomers vs The Same? Two Methods For Solving Problems
This post on how to solve "Enantiomers vs. Diastereomers vs. the Same?" problems (among other things) is a little long, so here's a partial index. The key distinctions: isomers vs. non-isomers, constitutional isomers vs. stereoisomers, and enantiomers vs. diastereomers. How to distinguish … [Read more...]
How To Do Well In Organic Chemistry: Advice From A Tutor
This is a guest post from Anna Tsimelzon, Ph.D., a university organic chemistry instructor and private organic chemistry tutor. You can learn more about Anna's tutoring services on her website, Tear Free Chemistry. My name is Anna Tsimelzon and I have been a private chemistry tutor for the past 5 … [Read more...]
Introduction to Peptide Synthesis
Today we'll go deeper on how to synthesize the most important amides of all - peptides - with an important contribution from protecting group chemistry. Peptide Bond Formation A "peptide bond" is an amide linkage (see Amides: Properties. Synthesis, and Nomenclature) that connects two amino acids, … [Read more...]
Site Undergoing A Major Marie Kondo – Pardon the mess
UPDATE, Feb 11. . Site is getting a total Marie Kondo, and not a moment too soon. Excited to show the results, hopefully soon. Note - mostly fixed, but major renovations are on the way. Thanks for your patience. JANUARY 25 - hey folks - thanks to all who brought this to my attention - many … [Read more...]
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