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Reaction of 9-fluorene propargylic alcohols and substituted-2-hydrazinopyridine using BF3·OEt2 as a Lewis acid catalyst afforded 9-fluorenlidene appended 2-hydrazinopyridine imine derivatives has been developed. The scope of the reaction is demonstrated by selecting a range of fluorene propargylic alcohols and substituted 2-hydrazinopyridine imines. All the synthesized molecules were characterized using various spectroscopic and analytical techniques including 1H NMR,13C NMR, and Mass spectrometry. A plausible reaction mechanism for forming title compounds via propargylic allenyl carbocation is postulated. The synthetic utility of products thus formed is demonstrated by utilizing Suzuki coupling. [ABSTRACT FROM AUTHOR]

A simple, efficient, and atom‐economical, one‐pot triple Michael Addition of activated alkenes to 2‐oxindole, 7‐aza‐2‐ indolone, and N‐methyl‐5‐bromo‐7‐aza‐2‐indolone has been developed. Significantly, multifunctionalities have also been achieved via one‐pot mixed Michael addition using the equimolar amount of two different activated alkenes. The reaction provided C‐3 and N‐functionalized carbon‐rich 7‐aza‐2‐oxindole derivatives. The scope of the reaction using diverse activated alkenes has been tested to provide the title compounds. The structure of the representative compounds has been established by the XRD method. Synthetic transformation of representative compounds is demonstrated to provide the respective 3‐spirooctane‐2‐oxindole derivatives in excellent yield. A plausible mechanism for cyclization is provided. [ABSTRACT FROM AUTHOR]

The combination of I2/CAN has emerged as a mild and powerful reagent for the oxidative Csp3‐Csp2 cleavage of 3,3′‐bis‐7‐azaindolylmethane to provide a quantitative combined yield of 3‐formyl and 3‐iodo‐7‐azaindole in a one‐pot reaction at RT. A plausible mechanism and characterization, including XRD, has been described. The synthetic transformations of title compounds were explored by reduction, Click, reductive amination, and Suzuki coupling reaction. [ABSTRACT FROM AUTHOR]

The mercuric acetate-pyridine-mediated cyclization reaction of aryl O-propargyl ethers of chalcones provided 8-phenyl-dibenzo[b,d]furan-1,7-diol and (E)-1-(4-hydroxy-3-styrylbenzofuran-2-yl)ethan-1-one via an unusual participation of O-propargyl group of ortho propargyl ethers is observed. The scope and limitations of the reaction and synthetic use of the products are provided. Based on control experiments and isolated products, a plausible reaction mechanism for forming unusual title compounds is provided. [ABSTRACT FROM AUTHOR]

A facile and efficient synthesis of 3‐spiro cycloalkene fused 7‐aza‐2‐indalones from 3,3′‐di‐ or N,3,3′‐tri‐ allyl/homoallyl/pentenyl 7‐aza‐2‐indalones via ring‐closing metathesis (RCM) using Grubbs‐II catalyst has been achieved. The scope of the reaction has been demonstrated by synthesizing spiro products of various ring sizes (n=5, 7, and 18), utilizing 2‐indalone/7‐azaindalone and various alkenylation agents such as allyl/homoallyl/pentenyl bromides as substrates. In addition to usual RCM products, a cross metathesis (CM) product was observed when the substrate was N,3,3′‐triallylated derivative from 2‐indalone. Notably, a macrocyclic, 18‐membered bis‐spirodiene of N‐methyl‐7‐azaindalone was observed by means of intermolecular ring‐closing metathesis (RCM‐RCM). Also, Structures of a few representative spiro‐annulated products were evidenced with single crystal XRD analysis. Furthermore, a plausible mechanism for the products is discussed. [ABSTRACT FROM AUTHOR]

A study on the activation of the NC-H bond of Morita-Baylis-Hillman adducts of N-substituted isatin with cerium ammonium nitrate (CAN) and saturated and unsaturated alcohols have been carried out. The choice of a Morita-Baylis-Hillman adduct for this study is screened with a number of adducts. A comparative and reactivity pattern study on NC-H activation of Morita-Baylis-Hillman adducts of N-substituted isatin derivatives viz. N-methyl, N-ethyl, N-methyl acetate, N-benzyl, N-propargyl, and N-isopropyl isatins have been carried out. Effect of aryl ring substitution has also been investigated. A plausible mechanism for the formation of the ether products has been outlined. Key words: cerium ammonium nitrate (CAN), Morita-Baylis-Hillman adduct, N-CH activation, functionalised ethers, nitration. Resume : On a effectue une etude sur l'activation, par le nitrate d'ammonium cerique (NAC), de la liaison NC-H d'adduits Morita-Baylis-Hillman d'isatine N-substituee et d'alcools satures et non satures. Le choix de l'adduit Morita-Baylis-Hillman pour cette etude est evalue avec un certain nombre d'adduits. On a aussi realise une etude comparative et une etude de patron de reactivite sur l'activation NC-H d'adduits Morita-Baylis-Hillman d'isatines N-substituees, entre autre par des groupes N-methyle, N-ethyle, N-methylacetate, N-benzyle, N-propargyle et N-isopropyle. On a aussi etudie l'effet de la substitution sur les groupes aryles. On propose un mecanisme plausible pour la formation d'ethers comme produits. Mots-cles : NAC, adduct de Morita-Baylis-Hillman, activation NC-H, ethers fonctionnalises, nitration., Introduction The C-H bond activation method is one of the challenging synthetic routes in organic synthesis. (1-12) Activation of C-H bonds particularly by oxidative processes (1-5) and by organometallic reagents [...]

An efficient method for the construction of the quinazolinone skeleton from the reaction of 9-(phenylethynyl)-9H-fluoren-9-ols with substituted 2-aminobenzamides catalyzed by boron trifluoride is achieved. The scope of the reaction with several 9-(phenylethynyl)-9H-fluoren-9-ols and substituted 2-aminobenzamides have been demonstrated. Repeating the reaction in the presence of NBS afforded 2-(bromo(9H-fluoren-9-ylidene)methyl)-2-phenyl-2,3-dihydroquinazolin 4(1H)one. The structure of representative compounds was established by the single-crystal XRD method. A plausible mechanism for the formation of the title compounds via the allene carbocation intermediate is proposed. The synthetic utility of products thus formed is demonstrated by utilizing Suzuki coupling and propargylation followed by a 'click' reaction. [ABSTRACT FROM AUTHOR]

Application of an alpha,beta-unsaturated keto group as the radical acceptor formed path A as one of the routes to the stereocontrolled preparation of functionalized, angularly fused tricyclic carbocycles from easily accessible 2-formylcycloalkanones. This path involved the preparation of tricyclo (7.4.0. 0 (4,9))tridecane, tricyclo(7.5.0.0 (4,9))tetradeacnae and tricyclo(7.3.0.0 (4, 9))dodecanes. A tricyclo(7.4.0.0 (4,9))tridecane skeleton results from the extremely convergent path B which is 95% stereoselective.