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Interaction of 3-(α- or γ-R-pyridin-2-yl)-1,2,4-triazines (R = Me, CO2Me) with arynes affords either the domino-transformation products, pyrido[1,2-a]indoles, or Diels-Alder reaction ones, isoquinolines. The influence of the nature and/or position of the substituent on the reaction pathway is discussed. [ABSTRACT FROM AUTHOR]

A sulfonic-acid-fu nationalize d ionic liquid is used as a Bronsted acid catalyst for the efficient synthesis of indole derivatives in good-to-high yields at room temperature under solvent-free conditions. The catalyst can he reused for ten consecutive runs without significant loss of activity. Key words: functionalized ionic liquid, indole derivatives, bis(indolyl)methanes, Michael adduct, recycling. On a utilise un liquide ionique a base d'acide sulfonique fonctionnalise comme catalyseur acide de Bronsted pour developper des syntheses efficaces de derives de l'indole obtenus avec des rendements allant de bons a eleves, dans des conditions sans solvant. Le catalyseur pent etre reutilise jusqu'a dix fois sans perte significative de son activite. Mots-cles : liquide ionique fonctionnalise, derives de l'indole, bis(indolyl)methanes, adduit de Michael, recyclage. [Traduit par la Redaction] Doi: 10.1139/V09-154, Introduction Michael reaction is one of the most important carbon-carbon bond-forming reactions. (1) The syntheses and the reactions of indole derivatives have received much interest for over a century because [...]

The theory of the firm under uncertainty has been traditionally studied using the expected utility approach. There are very few works done in this field of study using the risk-return approach despite the popularity of this dichotomy in the business world. This paper, therefore, applies various mean-risk models to the output decision making of a competitive firm facing uncertainty in the product price. The risk formulation used in this paper involves a pre-specified target level of profit, similar to those discussed in Fishburn (1977 and 1984). Furthermore, the measure of risk-aversion used in this model indicates the relative weight given by the agent to the risk component of the mean-risk objective function. The results of various mean-risk models are compared to those in the corresponding expected utility literature, and significant differences are found in many cases. One important difference is that whenever expected utility results require decreasing absolute risk aversion as a sufficient condition, the corresponding sufficient condition in the risk-return model of this paper is given by the condition that marginal cost is at least as large as the sum of average cost and average target level of profit. The results of this paper, in our opinion, are intuitively more appealing compared to the relatively abstract concept of decreasing absolute risk aversion., INTRODUCTION Traditionally, risk-return models have been used in portfolio theory. The theory of the firm under uncertainty has not been analyzed with the risk-return approach except for few works such [...]

This paper investigates the changing explanatory power of selected macroeconomic variables over aggregate stock returns as the timeframe changes from over-the-month to over-the-year. Using the same set of monthly observations from January 1970 to December 2004, we found that the explanatory power changes dramatically from less than 1 percent of variance in stock returns calculated on monthly basis to more than 84 percent of variance when point-to-point change is measured over one-year period. This finding is consistent with previous research [Fama (1981, 1990); Kaul (1957);Shah (1989); and Barro(1990)]. Further, the results from our study also provide an alternative to using high frequency data as in Flannery and Protopapadakis (2002) in order to improve explanatory power. Quite interestingly, it is also observed that lagged growth rate in industrial production (a proxy of overall economic activity) and rate of inflation contribute significantly to the explanatory power apart from own lagged value of stock returns, while the contributions of change in broad monetary aggregate and federal funds rate are negligible. An investigation of possible structural breaks or shifts during different time periods confirms that a significant shift in the slope seems to have occurred in 1992. Surprisingly, the oil shock period of 1979/80 and the tragedy of September 11, 2001 do not seem to have induced any significant structural changes in the relationships among the macroeconomic variables studied in this paper. Finally, the forecasting power of the model using only the lagged values of the regressors and the sample period of January 1970 to December 2003 to make unconditional out-of-sample forecast for the twelve months of 2004 has been tested. All tests show quite significant out-of-sample forecasting power of the model used., INTRODUCTION Numerous studies have been documented during last two decades in the empirical literature of financial economics that investigated the predictability of stock returns by lagged regressors. The regressors include [...]