Using transistor as switch in the "middle" of the circuit
It's ok to use an NPN in the 'middle' of the circuit. If you were to use mosfets, there could be problems with Vgs if used in the 'middle', the gate needs to be higher than the source or the mosfet will not turn on.

An NPN transistor will function like a mechanical switch, but will have a voltage drop across it similar to a diode. The NPN transistor most likely needs more current, with the 1k current limiter resistor, it would be wise to either lower the resistance or increase the voltage from 1.1V to 5V so the transistor can be fully on.