McCann, who was called up by England Under-16s earlier this summer, was one of the brightest prospects in the Sky Bet League Two club's academy.
He had been with his hometown club since the age of seven but the lure of the Premier League and Old Trafford proved too much.
The Sky Blues have received an undisclosed fee for the Coventry-born starlet and academy manager Richard Stevens said they could not stand in his way.
Stevens told Coventry's website: "When a big football club come knocking, and it is the club that Charlie supports, you must let him go and have that experience.
"We did not want to sell him, we did not need a fee for him even though there was a fee involved.
"He has been unbelievable for us, even making his England debut back in August.
"Charlie goes with complete support from me and the rest of the staff from the academy."
Source : PA
Source: PA