Students who lack academic maturity can sometimes feel overwhelmed in a fully flipped classroom. Here an alternative, the Semi-Flipped method, is discussed. Rural students, who face unique challenges in transitioning from high school learning to collegelevel learning, can particularly profit from the use of the Semi-Flipped method in the General Chemistry classroom. This method brings together preparation before class, active learning in class, and a supportive homework system, and it appears to have significant benefits both for students and for the instructor.

Benzyltrialkylgermane cation radicals were generated and spectroscopically characterized by nanosecond transient absorption spectroscopy. The germane cation radicals were found to rapidly react with nucleophiles (e.g., alcohols) in reactions that were first-order in cation radical and first-order in nucleophile. The geometries of the transition states for nucleophilic substitutions on benzyl-silane and -germane cation radicals were investigated by using the endocyclic restriction test. Cation radicals containing tethered nucleophiles that required endocyclic transition states with small angles between the bond being formed to the nucleophilic atom and the bond to the leaving group reacted ∼250 times more slowly than cation radicals with tethered nucleophiles where a large bond angle can be accommodated. The results are consistent with the nucleophile-assisted fragmentations proceeding through an inversion transition state.

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