Dropped phone in isopropyl alcohol now it wont turn on.

You somehow misread the article or read a wildly inaccurate article.

You can clean the board using isopropyl alcohol, not dunking the whole thing in it.

There is alcohol under the chips. Disconnect the battery and let it dry for a day or so. It will be just fine. Alcohol is slightly conductive and the chips dont like it. It will live. Just let it dry

Unfortunately, there are a large number of videos and articles on You Tube -- and elsewhere on the net -- that are totally fake or intentionally misleading. While some are written and produced by some very well meaning people, others are simply out there to wreak havoc. I'm sorry to say that you have fallen prey to one of those videos/articles. Dunking your phone in a container of alcohol -- typically people will use isopropyl alcohol -- is no different than dunking it in water. Isopropyl alcohol is typically 30~50% water. Which is about all you need to damage sensitive electronics. Even if you used denatured alcohol, you likely caused damage that you cannot see. Partly because you cannot see the underside of the components mounted on the board, or inside the many sub assemblies (camera, headphone jack, charging port, etc.). People tend to believe that alcohol does not leave any residue when it dries. Unfortunately, this is simply not the case.

Back in the day, we would use freon TF for our precision cleaning needs. Unfortunately, that stuff was banned many years ago, and with the demise of tape decks of any kind, a consumer friendly replacement isn't a big priority. However, I've had some recent success using naptha as a replacement. Naptha is highly flammable, but sold as many products. Lighter fluid, coleman stove fuel, and I'm told automotive map sensor cleaner, are either straight naptha, or a mix of naptha and mineral spirits. Coleman fuel and lighter fluid are both pure naptha.

My suggestion is that you disassemble the phone one more time, and carefully wipe down those parts that you can readily and easily see. Pay particular attention to any exposed contacts. Keep in mind to use a clean, LINT FREE rag or cloth. Never use a q-tip or paper towel. After you've done this, drop everything into a bag of rice and let it sit overnight. The rice will remove any residual moisture that may still exist. Remove the parts from the rice, one at a time (in the order that they need to be reassembled). Use a can of dust-off, or other canned air to blow away any dust that may be present from the rice and anywhere else. This time pay particular attention to all recessed or enclosed contact points. I cannot guarantee success, but it may well do the trick. I recently used this -- successfully --on my daughter's cell phone after she dropped it in the toilet.

I would suggest you use a hair dryer on low heat (so you don't melt any plastic items) and blow air into the open phone (back removed). This will vaporize any remianing alcohol that may be causing a problem. I used isopropyl alcohol to clean flux off boards for many years with a brush, no problem (it is normally 70% al but you can get 90%).

I'd say one of two things it's totally up to you how much you might need whatever info or data you might have in your phone like all your cat videos and ex girlfriend pics. Anyways why don't you plug in one of them otg adapters with a mouse and see how far you get with it might try recalibrating the touch or graphics settings. My Obama Android phone would get condensated from sweat when id leave it in my pocket while I worked. Then I dropped it so many times but only cracked it near the back button so it started ghosting back button presses on its own I was lucky to get half a text message before it would start back back back back. It was crazy. Finally it stopped responding then I finally got a new phone. The other day out of curiosity I threw the phone on and it was working normal wtf. So maybe just leave it alone for a while it might work. Or whatever. Or just roll it up in a pair of your best socks and throw that thing in the dryer on low heat a couple of times make some of that Rice you were using and eat while you wait.. I'm dying to know what the ending is gonna be. Good luck bud..