To keep your Canadian PR you need to be in Canada for 2 years in any 5 year period.
Usually Immigration would probably not consider moving only for employment as a valid reason to retain your PR status given generally that is considered a personal choice.
Usually the only possible exceptions might be if you have a spouse who is a Canadian citizen that you are accompanying or this happens to be a temporary assignment from a Canadian employer then returning to same employer in Canada although 5 years might be a stretch to be considered temporary.
There is no way unfortunately to predict or guarantee in advance how IRCC would react to anyone retaining their PR status although maybe an L1 visa by its nature is temporary assignment so may meet that condition. Assume that you may still be paid in Canada, pay taxes and be employed by the Canadian company but working temporarily for a US subsidiary.
