Unaware, oblivious, heedless, inattentive, unmindful, unaffected and insensible are all suitable synonyms for the phrase "unconscious of". These words describe situations in which someone is either not aware of something or simply ignoring it. Being unaware can be a result of many things like preoccupation, lack of interest, or just passive neglect. Unconscious of is often associated with emotions incited by this unawareness, like indifference or disinterest. If you're trying to convey that someone is oblivious or unattuned to something happening around them, then unconscious of and its corresponding synonyms can help express that message more effectively in your writing.