The Song of Solomon remains as one of the most lovely and mysterious books in the Bible. But, I could probably count on one hand the number of times I've heard it preached on in my lifetime.
The Book of Kings says that Solomon wrote 1005 songs. Only this one survives.
I came across an interesting study of the Song of Solomon and while it doesn't treat it as connected to eschatology studies, it may provide details from which we might develop connections to the rapture.
I really do think there is much to be gained by associating the story in the Song of Solomon with the rapture and the study found in the link below gives some food for thought as it looks at the song in an interesting light.