Jubilees 7:20

20 And in the twenty-eighth jubilee Noah began to enjoin upon his sons' sons the ordinances and commandments, and all the judgments that he knew, and he exhorted his sons to observe righteousness, and to cover the shame of their flesh, and to bless their Creator, and honour father and mother, and love their neighbour, and guard their souls from fornication and uncleanness and all iniquity. 21 For owing to these three things came the flood upon the earth, namely, owing to the fornication wherein the Watchers against the law of their ordinances went a whoring after the daughters of men, and took themselves wives of all which they chose: and they made the beginning of uncleanness. 22 And they begat sons the Naphidim, and they were all unlike, and they devoured one another: and the Giants slew the Naphil, and the Naphil slew the Eljo, and the Eljo mankind, and one man another. 23 And every one sold himself to work iniquity and to shed much blood, and the earth was filled with iniquity. 24 And after this they sinned against the beasts and birds, and all that moves and walks on the earth: and much blood was shed on the earth, and every imagination and desire of men imagined vanity and evil continually. 25 And the Lord destroyed everything from off the face of the earth; because of the wickedness of their deeds, and because of the blood which they had shed in the midst of the earth He destroyed everything.

Date: 150-100 B.C.E.
* Dates are based on scholarly estimates

Pseudo Jonathan Genesis 6:2

And it was when the sons of men began to multiply upon the face of the earth, and fair daughters were born to them; and the sons of the great saw that the daughters of men were beautiful, and painted, and curled, walking with revelation of the flesh, and with imaginations of wickedness; that they took them wives of all who pleased them. And the Lord said by His Word, All the generations of the wicked which are to arise shall not be purged after the order of the judgments of the generation of the deluge, which shall be destroyed and exterminated from the midst of the world. Have I not imparted My Holy Spirit to them, (or, placed My Holy Spirit in them,) that they may work good works? And, behold, their works are wicked. Behold, I will give them a prolongment of a hundred and twenty years, that they may work repentance, and not perish. Schamchazai and Uzziel, who fell from heaven, were on the earth in those days; and also, after the sons of the Great had gone in with the daughters of men, they bare to them: and these are they who are called men who are of the world, men of names.

Date: 300-1200 C.E.
* Dates are based on scholarly estimates