my heater core is leaking and my ac dont work so do u think i could hook the coolent lines throgh the condensor for heat then when i turn it on cool

Perhaps. I'm hesitant but the theory seems sound. Coolant is Glycal and 98% water. AC units use Polly Alkaline Glycol (PAG) Oil. I couldn't say how they will interact but I would suggest running some water through first. Your defrost won't work but it doesn't anyway right? When a heater box fails it goes to full heat and defrost. Good luck with your fix, let us know how it goes.