That is about it for drawing the ring-flip of chair conformations. Each Equatorial group becomes Axial and each Axial group becomes Equatorial.All the groups pointing up should still be pointing up regardless of being axial or equatorial.The atoms should stay where they are – left carbon on the left and right carbon on the right.There is NO such thing as a wedge is always axial or a dash is always equatorial!
If you haven’t covered that in your class yet, but the take-home message is: the direction for numbering atoms must be consistent.Īgain, in the beginning, you can choose any direction (clockwise or counterclockwise) but once there, you must follow it.ĭraw the other conformation of the chair (Ring-Flip): You can jump ahead and read about enantiomers. You can see they are non-superimposable mirror images, meaning no matter how you move them, you can’t make them be identical. Occasionally these conformations are found in rigid, fixed structures having cyclohexane subunits, either by design or in nature. This is a different molecule than what we are working with: take a limited look at the boat conformation (but not the twist boat or half-chair). Let’s do it here and see: If we number the ring starting from the OH and going counterclockwise (CCW), this is what we get: If you go in opposite direction numbering the atoms in the ring, for example, initially going clockwise and now-counterclockwise, you will draw the enantiomer of the cyclohexane (enantiomers are stereoisomers, so they are different compounds). This, unfortunately, happens in some YouTube videos as well (as I was referred to by one of my students) and students learn the wrong way. It is a common mistake to number the atoms inconsistently. Number the atoms starting wherever you want but, this is Important – you must follow the direction you had in Step 1:Īdd the groups based on the numbers pointing Up or Down as you labeled them in step 2: You can draw any of the two-doesn’t matter: “Up” and “Down” is relative as it depends on the direction you are looking from but let’s follow this notation.ĭraw a chair conformation. Label wedge groups as pointing Up and dash lines as pointing Down. Number the atoms in the ring (the starting point and the direction doesn’t matter). This means no bonds are broken and all the atoms stay where they are:Īssuming you have practiced drawing chairs, this is what you need to do to draw the ring-flip of any substituted cyclohexane: The ring-flip represents two conformations of the same compound that are obtained through rotation around single bonds. Notice that the carbon chains of these two chairs look like mirror images: One approach to master this is printing out a nicely drawn chair conformation and sketch it on a different sheet of paper placed on it:
#How to draw boat conformation on chem draw free#
There are different ways of drawing a chair conformation and you are free to choose the one you like – as long as at the end you have the structures correct.
The first thing you need to know before drawing the ring-flip of a chair cyclohexane is the correct conformation of the carbon-chain and the orientation of each axial and equatorial group: