The synthesis, structural, and spectroscopic characterization of four new coordinatively unsaturated mononuclear thiolate-ligated manganese(II) complexes ([MnII(SMe2N4(6-Me-DPEN))](BF4) (1), [MnII(SMe2N4(6-Me-DPPN))](BPh4)•MeCN (3), [MnII(SMe2N4(2-QuinoPN))](PF6)•MeCN•Et2O (4), and [MnII(SMe2N4(6-H-DPEN)(MeOH)](BPh4) (5)) is described, along with their magnetic, redox, and reactivity properties. These complexes are structurally-related to recently reported [MnII(SMe2N4(2-QuinoEN))](PF6) (2) Dioxygen addition to complexes 1-5 is shown to result in the formation of five new rare examples of Mn(III) dimers containing a single, unsupported oxo bridge: [MnIII(SMe2N4(6-Me-DPEN)]2-(μ-O)(BF4)2•2MeOH (6), [MnIII(SMe2N4(QuinoEN)]2-(μ-O)(PF6)2•Et2O (7), [MnIII(SMe2N4(6-Me-DPPN)]2-(μ-O)(BPh4)2 (8), [MnIII(SMe2N4(QuinoPN)]2-(μ-O)(BPh4)2 (9), and [MnIII(SMe2N4(6-H-DPEN)]2-(μ-O)(PF6)2•2MeCN (10). Labeling studies show that the oxo atom is derived from 18O2. Ligand modifications, involving either the insertion of a methylene into the backbone, or the placement of an ortho substituent on the N-heterocyclic amine, are shown to noticeably modulate the magnetic and reactivity properties. Fits to solid-state magnetic susceptibility data show that the Mn(III) ions of μ -oxo dimers 6-10 are moderately antiferromagnetically coupled, with coupling constants (2J) that fall within the expected range. Metastable intermediates, which ultimately convert to μ-oxo bridged 6 and 7, are observed in low-temperature reactions between 1 and 2 and dioxygen. Complexes 3-5, on the other hand, do not form observable intermediates, thus illustrating the effect that relatively minor ligand modifications have upon the stability of metastable dioxygen-derived species.

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West Virginia University College of Engineering and Mineral Resources and The EdVenture Group have partnered successfully over the past four years to increase the awareness and classroom applications of engineering curriculum through technology with 7 th-12 th grade students across the state of WV. Math and Science teachers from across the state have collaborated with education consultants, industry professionals, graduate students, and one another to gain knowledge and create units that focus on STEM careers and curriculum. The units, known as TIME (Tools for Integrating Math and Engineering) Kits, are stored electronically on a free teacher resource site for use in classrooms across the country. www.thesolutionsite.com The 12-hour units of instruction are developed during a week-long workshop that provides classroom teachers with the opportunity to work with engineering faculty, graduate assistants and industry experts. The model is based on providing time for teachers to learn, tools for teachers to use and strategies to assist them in focusing on and connecting engineering to STEM course work. By connecting university experts, industry experts and 7 th-12 th grade educators a new network has been created to link these groups and bring all areas of knowledge and application to classroom instructional units. All units are based on content standards, 21 st century skills, and a problem-based learning approach and translate regionally to other states Pre and post-assessments are administered to students who take part in a TIME Kit unit to gauge the acquisition of math and/or science concepts as well as attitudinal data concerning engineering as a career choice. This paper describes a sample TIME Kit for illustration. The paper also shows how, over three years, the partners have overcome roadblocks in teacher training, which teacher incentives to use and which to avoid, and how to ensure a solid program evaluation.