Question

Can someone help me draw these?

1. (1S)-5-(p-methylphenyl)cyclopent-2-enol

2. (Z,2R,7S)-2-hydroxy-7-methyl-3,8-dioxooct-4-enoic acid      

Answer 1

Note for assigning R/S

If last (4) priority is below the plane I.e., on dash the clockwise rotation of priority 1 2 and 3 gives R and counterclockwise rotation gives S

If last priority is above the plane I.e., on wedge then clockwise rotation of priority 1 2 and 3 gives S and counterclockwise rotation gives R configuration. That means what the configuration of a chiral carbon will be depends on where the last priority is located

P.S. priority of the atoms of chiral carbon is assigned according to CIP rule.

1. To draw The structures, the first thing we'll do the structures, the a 1 is to g draw the carbon skeleton The on parent carbon chain. 1S)-5-6-methylphenyl) Cyclopent-2-enel e the parent Carbon Chain is cyclopent-2-ene after drawing the skeleton umber the carbon as per your convenience. n 1/ OH 55 12 -> Cyclopent-2-eneal 2 3 now on 5th and 1st position respectively, but assign the stereochemistry of the Pro As we know that the last priority is my dashe below to the plane) we would get Therefore, the structure would be. Hz from the name we know that there is (p methylphenyl) and -oh !position respectively. but along with position we have to remistry of the 1st carbon, which is so a the last priority is Hydrogen, and If we put H on the bove the plane) we would get the socongigration . OH ar OHH :EH OH 2). (Z, 2R, 75)-2-hydroxy - 7-methyl-3,8-dioxooct-4-enoic acid again rest of the rules are some like draw the Parent Carbon chain and then put the substituents on their respective position. . Now, the thing we have to do is we have to put the hydroxy and methyl group along with their position and their configration. Plus. we have to make the alkem z . That means higher priority groups are on the same side of double bondo

Therefore the structure would be.. OH

You don't have to mention the numbering of parent carbon chain. I mentioned it just to make you understand. Please like the answer if it helped. Thank you. :)