I saw this is one of the molecules chosen for regular track, but not in progress for its synthesis by Enamine or others because multiple steps are required.
This is my proposed pathway:
Step 1/2 (intermediate not isolated)
4-piperidin-one + activating agent (eg. diphosgene, carbonyldimidazole, dimethyl carbonate), then unisolated intermediate is react then with piperidine. Urea obtained.
Step 2
Ketone is then reduced with sodium boron hydride to secondary alcohol.
Step 3
Reaction with methylsiocyanate (or other analogue reagent), to obtain the final carbamate
Submitted molecule at this link:
https://covid.postera.ai/covid/submissions/595fac82-7ea5-49a4-8881-97f95024c4fb