  Using self dual Ashtekar variables, we investigate (at the effective level)
the spherically symmetry reduced model of loop quantum gravity, both in vacuum
and when coupled to a scalar field. Within the real Ashtekar-Barbero
formulation, the system scalar field coupled to spherically symmetric gravity
is known to possess a non closed (quantum) algebra of constraints once the
holonomy corrections are introduced, which forbids the loop quantization of the
model. Moreover, the vacuum case, while not anomalous, introduces modifications
which are usually interpreted as an effective signature change of the metric in
the deep quantum region. We show in this paper that both those complications
disappear when working with self dual Ashtekar variables, both in the vacuum
case and in the case of gravity minimally coupled to a scalar field. In this
framework, the algebra of the holonomy corrected constraints is anomaly free
and reproduces the classical hypersurface deformation algebra without any
deformations. A possible path towards quantization of this model is briefly
discussed.
