Reaction of diarylnitrilimines with 3,3-dimethyl-2-indanone enamines; the first example of a stable zwitterionic nitrilimine–enamine cycloadduct

An Efficient One Pot Synthesis of New Indanopyrazoline and Indanopyrazole Derivatives

“…This choice was based on previous results [36,37] which show that a secondary amino group is very essential leaving group in [3+2] cycloaddition. The reaction leads to a mixture of two products, the 4H-3a,8b-dihydro-indeno[2,3-d]pyrazolines 3ad-cf (45-60 %) and the derivatives 4H-indeno[2, 3-d]pyrazoles 4 (30-38 %, see Table 1).…”

“…Under these conditions, only the pyrazoles were isolated, resulting from the loss of the amino group in the acidic reaction medium from the intermediate pyrazolines. In a preliminary note, some members of our group have already reported the reaction of C-p-anisyl-N-phenylnitrilimine towards 3,3-dimethylindan-1-one at benzene reflux [37]. For the first time, we have now succeeded to isolate and to characterize the pyrazolines 3 bearing a cyclic amino-substituent.…”

Drug design of new antitubercular agents: 1,3-dipolar cycloaddition reaction of arylnitriloxides and 3-para-methoxy-benzylidene-isochroman-4-ones

“…In our earlier studies of the dipolar 1,3-cycloaddition reaction, we investigated the action of diarylnitrilimines on dihydroquinoleine derivatives, 7 indene, 8 and the 3-methoxycarbonyl-4H-1-benzopyran-4-one, in which the dipolarophilic site is endocyclic. 9 We also studied the regionand the stereochemistry of the reaction of diarylnitrilimines with the 2-arylidene-indan-1-ones, 10 3-arylidene-tetraline-4-ones, [11][12] 3-arylidene-isothiochroman-4-ones, 13 and lately the 3-toluidene-2,3-dihydro-4(1H)-isoquinolone, 14 where the dipolarophilic site is exocyclic.…”

Synthesis of new spiro‐[isothiochromene‐3,5′‐isoxazolidin]‐4(1H)‐ones

“…The reaction occurs by a 1,3-dipolar cycloaddition mechanism that leads to the regiospecific formation of various spiroisoxazolidines (7)(8)(9)(10)(11)(12)(13). Spiro-isoxazolines derivatives have emerged in recent years as candidates for drugs due to their herbicidal, plant-growth regulatory and antitumor activity [1,2].…”

“…In our earlier studies of the 1,3-dipolar cycloaddition reactions, we investigated the action of diaryl-nitrilimines on dihydroquinoleines [7], indene [8] and the benzopyran-4-ones [9] in which the site of dipolarophiles is endocyclic. We also studied the regio-and the stereochemistry of the reaction of diaryl-nitrilimines with the 2-aryliden-indan-1-ones [10], 3-aryliden-tetraline-4-ones [11,12], 3-aryliden-isothiochroman-4-ones [13] and lately some isoquinolones [14], where the site of the dipolarophiles is exocyclic.…”