.NET MVC one to one relationhsip

Question

I am designing a Room Planner and Scheduler for university classes in ASP.NET 5 using c#. Currently, I have a model for university classes and a model for Timeslots.

It should be possible to create them independent of each other without having a connection at first. It should then be possible to assign each timeslot exactly one class or each class a timeslot.

What would be the best way to implement this connection? I thought about having some kind of intermediate / junction table but I want to avoid that a class can take place in more than one classroom and vice versa.

public class SchoolClass
    {
        public int Id { get; set; }
        public String Name { get; set; }

    }

public class Timeslot
    {
        public int Id { get; set; }
        public bool Occupied { get; set; }

        public Room Room { get; set; }
        public int RoomId { get; set; }

        public Weekday Weekday { get; set; }

        public TimeSpan Start { get; set; }
        public TimeSpan End { get; set; }

    }

Any help is much appreciated since I'm kinda stuck on the implementation