Is this Fischer Projection of (3R, 4S)-3-ethyl-3,4-dimethyl-1-hexene wrong? (3R, 4S)-3-ethyl-3,4-dimethyl-1-hexene

Draw the Fischer Projection of the compound above.

Here is the answer:



Is there a mistake at the upper stereocenter? I think so.
Is there a mistake at the upper stereocenter?


Yes you are thinking correct, the R configuration will be the diastereomeric pair of this compund, the second chiral carbon is in correct configuration. Don't you want to ask why?