Use cpvc and copper threaded adapters as per previous posts. DO NOT
use pipe dope on ANY plastic threads. Many pipe dopes will soften
plastic, causing a leak and possible catastrophic failure. Use several
wraps of teflon tape instead. The ONLY pipe dope I have seen that does
not soften plastic fittings is Gasola. If you get it on your clothes,
it will not wash off. Also, when you solvent weld the pvc fitting,
make sure you use PVC cleaner (also called primer) on the CPVC pipe and
fitting per the directions on the cans of glue and cleaner. If you
don't, the plastic joint may fail in a couple of years.

Stretch