17. Use OsO4 and D2O2 -> Syn addition of OD
Or you can use cold, dilute KMnO4, followed with -OD, D2O.
15, 16. Use a peroxyacid (peroxyacetic acid, MCBPA) to form an epoxide ring, then use D3O to open the ring and get anti-addition of OD
18. Pd/BaSO4, quinoline
Not sure about 19
20. 2 D2 and a metal catalyst like Pt, Pd, or Raney nickel