The 415 gear is too low ilvl to be converted w.r.t season 2 now. Only the 428 gear from the weekly quest (along with the weekly reward from the timerifts) and be converted. Sadly they stay as the LFR appearances from season 2, even if you upgrade them all the way to 450.
Currently the catalyst only provides the following raid mog sets
Season 1:
LFR via VotI LFR drops
Normal via 2/3 primalist gear or VotI normal / S1 world bosses
Heroic via 3/3 Primalist gear or VotI heroic
Mythic via VotI Mythic drops
Season 2:
LFR via 428 - 450 Dreamsurge / time rift gear (S3 adventurer rank) or LFR Aberrus
Normal via normal Aberrus / S2 world boss
Heroic via heroic Aberrus
Mythic via Mythic Aberrus
Season 3:
LFR via Veteran rank 1-4 gear
Normal via Veteran rank 5-8 OR Champion rank 1-4 gear
Heroic via Champion rank 5-8 OR Hero rank 1-4 gear
Mythic via Hero rank 5-6 OR myth 1-4 gear.