We study N=1 compactification of IIB supergravity to AdS4. The internal
manifold must have SU(2)-structure. By putting some restrictions on the SU(2)
torsion classes, we can perform an exhaustive scan of all possible solutions on
group manifolds. We show that sourceless solutions don't exist and that the
presence of O5 and O7 orientifolds is mandatory. We also find a new solution
and relate it by T-duality to a known type IIA solution with O6 planes.Comment: 22 pages, (v2) : Appendix on the name of the solvmanifold added,
references updated, NS Bianchi Identity rewritte