Synthesis of Spirobicyclic Pyrazoles by Intramolecular Dipolar Cycloadditions/[1s, 5s] Sigmatropic Rearrangements. - Dimirjian CA; Castiñeira Reis M; Balmond EI; Turman NC; Rodriguez EP; Di Maso MJ; Fettinger JC; Tantillo DJ; Shaw JT (Organic letters, 2019)