Diasetereocontrol in Cyclohexyl Systems

Question 1

reactions of flexible cyclohexanes

Answer 1

Nu can attack equatorially or axially, axial attack disfavoured for anything other than H-, equatorial attack less sterically hindered so usually major product

Question 2

reactions of 6-membered rings with trigonal C

Answer 2

proceeds via chair-like transition state, overrides sterics

Question 3

advantages of proceeding via chair-like TS

Answer 3

allows for selective formation of less stable product which proceeds via more stable TS