Synthesis of a series of novel fused pyrazolines and pyrazoles has been accomplished in good yields by regioand diastereoselective 1,3-dipolar cycloaddition of enamines of indan-1-one 1a-c towards C-aryl-N-phenylnitrilimines 2d-f. The structure of the cycloadducts was elucidated by 1D and 2D NMR studies.

Synthesis of a series of cyclic fused‐isoxazolines has been accomplished by regioselective and diastereoselective 1,3‐dipolar cycloaddition of 3‐methylindan‐1‐one enamines (1a, 1b, 1c) and 3‐phenylindan‐1‐one enamines (2a, 2b, 2c) to arylnitrile oxides (3d, 3e, 3f, 3g, 3h). The structure of the cycloadducts was elucidated by 1H and 13C NMR spectroscopy. The proposed regio‐ and stereochemistry of fused‐compounds (4) and (5) has also been corroborated by two single‐crystal X‐ray diffraction studies carried out on 4‐methyl‐8b‐morpholinyl‐3‐(p‐tolyl)‐4H‐3a,8b‐dihydroindeno[2,3‐d]isoxazoline (4be) and 3‐(p‐anisyl)‐4‐phenyl‐8b‐pyrrolidinyl‐4H‐3a,8b‐dihydroindeno[2,3‐d]isoxazoline (5af) and by means of density functional theory calculations.

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Dipolarophiles (I) react with ethyl diazoacetate (II) at the exocyclic double bond of (I), regardless of the electronic nature of the p‐substituents on the aryl group of (I), to provide the single spiro‐compounds (III).

1,3-Dipolar Cycloaddition Reactions of Indan-1-one Enamines Across Arylnitrile Oxides Leading to Novel Cyclic Isoxazoline Derivatives. -A series of cyclic fused-isoxazolines is obtained by regioselective and diastereoselective 1,3-dipolar cycloaddition of enamines (I) and (IV) to arylnitrile oxides. -(JELIZI, H.; WANNASSI, N.; EL BAKER RAMMAH, M.; CIAMALA*, K.; KNORR, M.; ROUSSELIN, Y.; KUBICKI, M. M.; STROHMANN, C.; ENESCU, M.; J. Heterocycl. Chem. 51 (2014) 2, 383-391, http://dx.