I'd start by looking here
Shop OEM replacement parts by symptoms or model diagrams for your DeWALT DCD740B 20V Drill/Driver Type 1!
www.ereplacementparts.com
Then finding a similar dewalt impact driver, and see if the noses are in any way compatible.
Shop OEM replacement parts by symptoms or model diagrams for your DeWALT DCF787 20v Max Cmpct Brushless Impact Driver (Type 1)!
www.ereplacementparts.com
I'd say no, get away from an impact, the anvil will be different.
Looking at the back of the chuck, its a 1/2-20 thread, and all the hex to 1/2-20 are the wrong gender on both ends, made to mount a wheeel of some nature
That train of thought quickly devolves into plumbing fixtures