Reactivity of the two classes of very weak donors R(2)XO(2) (X = S, R = Me (1) and Ph (2); X = Se, R = Me (3) and Ph (4)) have been studied. Coordination properties of sulfones and selenones in solution and in the gas phase have been compared for the first time using a model bidentate metal complex, [Rh(2)(O(2)CCF(3))(4)]. Two coordination modes, bridging mu(2)-O,O' and terminal eta(1)-O, have been detected. These types of binding were realized in two series of sulfone and selenone metal complexes, polymeric mono-adducts [Rh(2)(O(2)CCF(3))(4).(R(2)XO(2))]( infinity ) (X = S, R = Me (1a); R = Ph (2a); X = Se, R = Ph (4a)) and discrete bis-adducts [Rh(2)(O(2)CCF(3))(4).(R(2)XO(2))(2)] (X = S, R = Ph (2b); X = Se, R = Me (3b)). The compositions and structures of new compounds have been confirmed by NMR and IR spectroscopy, chemical analyses, and X-ray diffraction studies. Compounds 3b and 4a are the first crystallographically characterized metal complexes having selenone ligands coordinated to the metal centers. Preparation and X-ray study of analogous metal complexes of sulfone and selenone ligands allow, for the first time, tracking the structural changes induced by metal coordination. In addition, the X-ray structure of dimethyl selenone, Me(2)SeO(2) (3), an analogue of Me(2)SO(2), has been determined. Geometries of coordinated sulfone and selenones ligands have been compared with those of the corresponding "free" molecules.
IntroductionHomogeneous transition metal catalyzed reactions have been very well studied over the past 50 years. The metal complexes used to accomplish these reactions have typically included noble transition metals or fi rst row metals. Due to the cost and pathogenicity of these noble metals, the development of new catalytic routes using non -precious metals is an active area of research. In this chapter, a review of the use of selected cobalt and nickel species towards catalytic reactions analogous to those seen with noble metals is presented. Catalysis with CobaltTransition metal catalyzed hetero -annulation provides a useful and convenient tool for the construction of N -heterocycles [1] . Quinolines are of special interest in that they display attractive applications in pharmaceuticals and are synthetic building blocks [2,3] . Catalytic processes employing palladium [4 -6] , rhodium [7 -9] , ruthenium [10 -14] , and iron [15] have been studied and developed to synthesize quinoline skeletons. There are fi ve common methods used to prepare substituted quinolines: the Skraup reaction [16] , the Doebner -Von Miller reaction [17] , the Conrad -Limpach reaction [18] , the Friedlaender reaction [19,20] , and the Pfi tzinger reaction [21,22] . All fi ve of the reactions require environmentally unfriendly acids or bases, high temperatures, or harsh conditions. Quinoline yields are usually low due to numerous side reactions. Even though much work has been done to fi nd catalytic routes to quinolines, the use of non -precious metals remains an active area of research.Recently, Jones et al. have published work on the conversion of diallylanilines and arylimines to quinolines [23,24] . It was found that N -allylaniline, when heated in the presence of 10 mol% Co 2 (CO) 8 and 1 atm of CO at 85 ° C, leads to the selective formation of 2 -ethyl -3 -methylquinoline (Equation (6.1) ). Aniline and propene 6 Catalysis Without Precious Metals. Edited by R. Morris Bullock
National employment data forecasts a significant need for graduates in the STEM disciplines for middle-income American jobs. If the American labor force is to keep pace with the global economy, it is critically important that American higher education increase STEM degree production. Currently, minority populations lack access and thus opportunity for success in higher education, but, among them, Hispanic groups account for about 59 million Americans, are the youngest demographic, and have the highest growth rate of any ethnic group. Hispanic students are inadequately represented in higher education enrollment numbers, graduation rates, graduate degree attainment, and STEM degree attainment. While only 14% of American institutions of higher education are designated as Hispanic Serving Institutions (HSIs), 64% of Hispanic American college students attend an HSI. As a result, HSIs are in a unique position to improve student success in STEM disciplines. A statistical analysis of the grades of Hispanic and White students in an introductory STEM course, Calculus I, at two Florida HSI universities and two non-HSI universities, revealed 1) white students significantly outperformed Hispanic students in Calculus I at State of Florida non-HSIs and 2) white students did not outperform Hispanic students in Calculus I at State of Florida HSIs.
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