A second picture of the drying of the leaves. Also when I water I soak the plants until water is coming out the bottom of the pot to prevent mineral build up.

I wonder if it may be the sun burning the leaves. There will be someone who will pop in and let you know.
Kind regards
Averil UK

adeniums are to be kept under bright sunlight but toomuch heat can burn the leaves and dehydrate them so this may be the reason according to my knowledge. so keep your plant in shade and also avoid water clogging which will cause fungal infections in the roots , of course you would know these things.

Hi,
Remember your plant is recently potted and will need some time to become fully established, untill then it is natural to drop a few older leaves, I'm sure they will soon be replaced.
Happy growing,
Brian UK.

Thanks to all who responded to my post.

When I repotted my DR I had the initial leaf drop. Lost almost 1/3 of the my leaves. But then she stabilized until the recent heat wave. Which leads me to believe it was the extreme heat. And yes I'm a little worried about over watering but have read that some people water twice a day in some places with extreme heat. I haven't gotten that bad yet. I'm down to every other day or two full days of sunlight and heat. I don't believe I will see very many days under 100+. At what point should do I need to worry about the heat.

Thanks again for your timely responses,
JR