A novel protocol for the construction of tricyclic chromenoisoxazoline frameworks via an intramolecular 1,3-dipolar nitrile oxide cycloaddition (INOC) reaction using Baylis-Hillman derivatives is described for the first time. The INOC reaction leads to a novel class of angularly substituted fused tricyclic chromenoisoxazolines, with the creation of two rings and two adjacent stereocenters, one of them being an all-carbon quaternary center, in a unique fashion. The tricyclic chromenoisoxazolines are obtained in a highly stereoselective fashion with good yields.