Here’s my spoon feed of the day for making THC-P from THC.
First Step: mCPBA epoxidation of the allylic system.
Step 2: a.) NBS Bromination of Benzylic position. b.) elimination of benzyl bromide to conjugated alkene. c.) allylic NBS bromination of alkene. d.) elimination of benzyl bromide to conjugated diene. e.) allylic NBS bromination of diene.
Step 3: Ethyl grignard of terminal allylic bromide.
Step 4: Reduction of diene via standard Pd/C/H2 reduction, while simultaneously reducing epoxide with a fancy Au system. https://pubs.rsc.org/en/content/articlelanding/2021/cy/d0cy01695k