191 research outputs found

    Critical Perspective: Named Reactions Discovered and Developed by Women

    Get PDF
    Named organic reactions. As chemists, we’re all familiar with them: who can forget the Diels−Alder reaction? But how much do we know about the people behind the names? For example, can you identify a reaction named for a woman? How about a reaction discovered or developed by a woman but named for her male adviser? Our attempts to answer these simple questions started us on the journey that led to this Account. We introduce you to four reactions named for women and nine reactions discovered or developed by women. Using information obtained from the literature and, whenever possible, through interviews with the chemists themselves, their associates, and their advisers, we paint a more detailed picture of these remarkable women and their outstanding accomplishments. Some of the women you meet in this Account include Irma Goldberg, the only woman unambiguously recognized with her own named reaction. Gertrude Maud Robinson, the wife of Robert Robinson, who collaborated with him on several projects including the Piloty−Robinson pyrrole synthesis. Elizabeth Hardy, the Bryn Mawr graduate student who discovered the Cope rearrangement. Dorothee Felix, a critical member of Albert Eschenmoser’s research lab for over forty years who helped develop both the Eschenmoser−Claisen rearrangement and the Eschenmoser−Tanabe fragmentation. Jennifer Loebach, the University of Illinois undergraduate who was part of the team in Eric Jacobsen’s lab that discovered the Jacobsen−Katsuki epoxidation. Keiko Noda, a graduate student in Tsutomu Katsuki’s lab who also played a key role in the development of the Jacobsen−Katsuki epoxidation. Lydia McKinstry, a postdoc in Andrew Myers’s lab who helped develop the Myers asymmetric alkylation. Rosa Lockwood, a graduate student at Boston College whose sole publication is the discovery of the Nicholas reaction. Kaori Ando, a successful professor in Japan who helped develop the Roush asymmetric alkylation as a postdoc at MIT. Bianka Tchoubar, a critically important member of the organic chemistry community in France who developed the Tiffeneau−Demjanov rearrangement. The accomplishments of the women in this Account illustrate the key roles women have played in the discovery and development of reactions used daily by organic chemists around the world. These pioneering chemists represent the vanguard of women in the field, and we are confident that many more of the growing number of current and future female organic chemists will be recognized with their own named reactions

    Manganese(II) Complexes with Schiff Bases Immobilized on Nanosilica as Catalysts of the Reaction of Ozone Decomposition

    Get PDF
    In this article, we submit the description of synthesis and identification of manganese(II) complexes with pyrogenic nanosilica-immobilized (d av = 10 nm; S sp = 290 m2/g) hydroxyaldimine ligands (Mn(L)2/Si): salicilaldiminopropyl (L1); 5-bromosalicilaldiminopropyl (L2); 2-hydroxynaphtaldiminopropyl (L3); 2-hydroxy-3-methoxybenzaldiminopropyl (L4); 2-hydroxy-3,5-dichloroacetophenoniminopropyl (L5); and 4-hydroxy-3-methoxybenzaldiminopropyl (L6). The ligands and complexes were characterized by UV-VIS and IR spectrometry. Nanocomposites consisting of complexes Mn(L)2/Si showed a high catalytic activity in low-temperature ozone decomposition in the range of concentrations between 2.1 × 10−6 and 8.4 × 10−6 mol/l. The number of catalytic cycles increased for isostructural pseudotetrahedral complexes Mn(L)2/Si (L1–L5) in the following order: Mn(L3)2 >> Mn(L4)2 > Mn(L1)2 > Mn(L2)2 > Mn(L5)2. In the case of pseudooctahedral complexes with L6, the change of coordination polyhedral does not influence the kinetics and stoichiometric parameters of the reaction

    Próba wykorzystania pasm włókien pozyskanych z małowymiarowego drewna wierzbowego do produkcji płyt wiórowych

    No full text

    On the mechanism of carboxylic acid co-catalyst assisted metalloporphyrin oxidations

    Get PDF
    The role of the carboxylic acid as co-catalyst in metalloporphyrin catalytic hydrogen peroxide oxidations is discussed, taking into account its dependence on the ratio relatively to the catalyst. The catalytic efficiency and stability of the catalyst in the presence of an excess of carboxylic acid suggests that a metallo-acylperoxo complex can be the effective oxidation intermediate.http://www.sciencedirect.com/science/article/B6TGM-42G6XGY-4/1/0ef5cfc94471f6985d77385ef339282

    How Writing Contributes to Learning: New Findings from a National Study and Their Local Application

    No full text
    Writing ability is among the most valued outcomes of a college education. Always included in conceptions of a liberal education, writing is also one of the most highly desired skills across business and industry (see Hart 2015; Burning Glass Technologies 2015). Since the 1970s, writing specialists have intensified their theorizing, research, and advocacy of institution-level initiatives aimed at improving students’ writing abilities. These efforts have produced, among other things, writing-intensive (WI) courses and writing-across the-curriculum (WAC) and writing-in-the-disciplines (WID) programs. In 2008, the Association of American Colleges and Universities (AAC&U) underscored the importance of effective writing pedagogy by including writing-intensive courses in its list of high-impact educational practices (Kuh)

    New insights into the mechanism of molybdenum-catalyzed asymmetric alkylation*

    No full text
    Abstract: The major features of the catalytic cycle, including structures of key intermediates, have been determined for the molybdenum-catalyzed asymmetric alkylation. The crystal structure of the π-allyl intermediate exhibits 3-point binding of an anionic ligand. Based on NMR analysis, this species adopts in solution a structure consistent with that observed in the solid state. For the allylic alkylation, the crystal structure predicts the opposite stereochemistry vs. that observed experimentally, which suggests that either the reaction proceeds via a minor isomer (Curtin-Hammett conditions) or with retention of configuration. In addition, CO transfer, promoted by Mo(CO) 6 , has been found to play a key role in catalyst turnover
    corecore