Direct driving the Mosfet  from the CMOS-Monoflop is not optimal as the capacity of the gate deteriorates the pulse somewhat. It seems that the usual way would be to use a gate driver IC. But before ordering one I wanted to try it out first with a discrete circuit from Mr. T's: 3 Simple MOSFET Drive Circuits

I opted for the "Cascode-Driver", which works very well in my case. It also works for a High-Side P-Channel Mosfet when changing npn to pnp transistors, reversing the polarity and driving the circuit using the non inverting Output of the Monoflop.

Additionally I also added a small resistor in series with the wire to decrease the impulse load of the power supply.