That is not actually scheduling it for 1 hr and 1 minute in the future but rather for 1:01 am in the morning every day. Probably not what you intended.
If you want to run it just 1 hour and 1 minute in the future, you could do something like the following:
Datetime futureTime = Datetime.now().addHours(1).addMinutes(1);
String futureTimeCronString = '0 ' + futureTime.minute() + ' ' + futureTime.day() + ' ' + futureTime.month() + ' * ' + futureTime.year();
System.schedule('OrderApprovalDeadlineScheduler', futureTimeCronString, new OrderApprovalDeadlineScheduler());
This has not been tested but should be close to what you want. It builds up a Cron Expression for a specific date and then schedules the class to run. It does assume that your
OrderApprovalDeadlineScheduler class implements the
However, I would caution against actually setting up scheduled jobs from a trigger. It is potential that the trigger will get called over 100 times before one of the jobs runs, at which point you will have hit a governor limit and the process will fail. See the documentation here