I have seen from a few places which claim that they have found a letter written from Aristotle to Alexander the great . In the letter Aristotle laments about the fact that he wasted so much time on nonsense while he could have been studying the Torah. Is there any validity to this. I find this very hard to believe since the Rambam would have made mention of this and he did not.
This article in the Jewish Encyclopedia details Aristotle's place in Jewish legends.
The closest evidence connecting Aristotle to Jewish teachings, that the article mentions is that Josephus (Contra Apionem, I, 22) quotes a (supposed) work of Clearchus of Soli which mentions his mentor Aristotle's comments about a Jew he met. Aristotle is quoted as saying:
What this Jew said merited admiration and showed philosophical erudition...These Jews are derived from the philosophers of India..Now this man, who had been the guest of many people, had come down from the highland to the seashore [Pergamus]...And as he had had intercourse with a large number of sages, he imparted to us more knowledge of his own.
That is, apparently Aristotle learned from a Jew and valued his teachings.
The letter you mention in the question seems to be a letter first referenced by Jews in the late 14th century, in which he:
recant[s] all his previous philosophic teachings, having been convinced of their incorrectness by a Jewish sage. He acknowledges as his chief error the claim that truth is to be ascertained by the reasoning faculty only, inasmuch as divine revelation is the sole way to truth.
As one would expect, the aforementioned article notes that the letter is apocryphal.