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To date, no CCC‐NHC pincer complexes of Re have been reported in the literature. The first CCC‐NHC pincer complex of Re is reported. It was fully characterized by¹H and¹³C nuclear magnetic resonance (NMR) spectroscopy, mass spectroscopy, elemental analysis, and X‐ray crystallographic methods to determine the molecular structure. It was synthesized via transmetallation from an isolated Zr precursor and was found to be air stable. The catalytic activity of the CCC‐NHC Re(I) pincer complex was demonstrated for the borrowing hydrogen coupling reaction between benzylic ketones and primary alcohols to generate a new C–C bond in an environmentally friendly catalysis requiring no activating groups for the alcohol functionality. This borrowing hydrogen coupling reaction produced a stoichiometric amount of water as the only by‐product and did not require the conversion of the primary alcohol to a leaving group. A broad range of substrates was examined, and isolated yields from 53% to 92% were obtained. A catalytic cycle for the CCC‐NHC Re(I) pincer complex catalyzed borrowing hydrogen coupling reaction is proposed.

 

Given the importance of broadening participation in the field of computing, goals of supporting personal expression and developing a sense of belonging must live alongside the goals of conceptual knowledge and developing disciplinary expertise. Integrating opportunities for students to be creative in how they enact computing ideas plays an important role when designing curricula. We examine how student creativity, as expressed through theme and the use of costumes, backdrops, and narrative in Scratch projects, is affected by using a themed starter project. Starter projects are Scratch projects that include a set of sprites and backdrops aligned to a theme (e.g. baseball), but no code. Using within-group and between- group comparisons, we establish a baseline of what students do when they are given a starter project and explore how their projects differ in the absence of a starter project. This work contributes to our understanding of the impacts of structured elements within open-ended learning tasks and how we can design computer science learning experiences for students that promote opportunities for self-expression while engaging them in computing. 

As computer science instruction gets offered to more young learn- ers, transitioning from elective to requirement, it is important to explore the relationship between pedagogical approach and student behavior. While different pedagogical approaches have particular motivations and intended goals, little is known about to what degree they satisfy those goals. In this paper, we present analysis of 536 students’ (age 9-14, grades 4-8) work within a Scratch-based, Use-Modify-Create (UMC) curriculum, Scratch Encore. We investigate to what degree the UMC progression encourages students to engage with the content of the lesson while providing the flexibility for creativity and exploration. Our findings show that this approach does balance structure with flexibility and creativity, allowing teachers wide variation in the degree to which they adhere to the structured tasks. Many students utilized recently-learned blocks in open-ended activities, yet they also explored blocks not formally taught. In addition, they took advantage of open-ended projects to change sprites, backgrounds, and integrate narratives into their projects.