Single-electron transfer (SET) oxidation of ionic hypervalent complexes, in particular alkyltrifluoroborates (Alkyl-BF 3 À ) and alkylbis(catecholato)silicates (Alkyl-Si(cat) 2 À ), have contributed substantially to alkyl radical generation compared to alkali or alkaline earth organometallics because of their excellent activitystability balance. Herein, another proposal is reported by using neutral metalloid compounds, Alkyl-GeMe 3 , as radical precursors. Alkyl-GeMe 3 shows comparable activity to that of Alkyl-BF 3 À and Alkyl-Si(cat) 2 À in radical addition reactions. Moreover, Alkyl-GeMe 3 is the first successful group 14 tetraalkyl nucleophile in nickel-catalyzed cross-coupling. Meanwhile, the neutral nature of these organogermanes offset the limitation of ionic precursors in purification and derivatization. A preliminary mechanism study suggests that an alkyl radical is generated from a tetraalkylgermane radical cation with the assistance of a nucleophile, which may also result in the development of more non-ionic alkyl radical precursors with a metalloid center.

Herein, we report a general strategy for the rational design of an efficient organic photocatalyst, and we describe a robust method for the direct C(sp 3 )−H carbamoylation of saturated aza-heterocycles under mild conditions by using a naphthalimide (NI)-based organic photocatalyst. This protocol provides a concise and practical approach for the rapid installation of a valuable amide bond onto pharmaceutically useful saturated aza-heterocycles to access a wide range of cyclic α-amino amides. A series of mechanism investigations have demonstrated this transformation undergoes a visible-light photocatalytic, oxidative Ugi reaction process.

Single-electron transfer (SET) oxidation of ionic hypervalent complexes, in particular alkyltrifluoroborates (Alkyl-BF 3 À ) and alkylbis(catecholato)silicates (Alkyl-Si(cat) 2 À ), have contributed substantially to alkyl radical generation compared to alkali or alkaline earth organometallics because of their excellent activitystability balance. Herein, another proposal is reported by using neutral metalloid compounds, Alkyl-GeMe 3 , as radical precursors. Alkyl-GeMe 3 shows comparable activity to that of Alkyl-BF 3 À and Alkyl-Si(cat) 2 À in radical addition reactions. Moreover, Alkyl-GeMe 3 is the first successful group 14 tetraalkyl nucleophile in nickel-catalyzed cross-coupling. Meanwhile, the neutral nature of these organogermanes offset the limitation of ionic precursors in purification and derivatization. A preliminary mechanism study suggests that an alkyl radical is generated from a tetraalkylgermane radical cation with the assistance of a nucleophile, which may also result in the development of more non-ionic alkyl radical precursors with a metalloid center.

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Considerable research attentions have recently been paid toward a mobile manipulator (a robot arm standing on a mobile platform) due to its extended workspace beyond the manipulator reach. Mobile manipulators have a wide range of potential applications where it is desirable to achieve higher degree of flexibility in transport and handling task. However, a vast number of research publications only focus on trajectory planning. This preliminary research work presents dynamic modeling and analysis of a mobile flexible robot arm with aims to provide insights for the design and control of such mobile robot manipulators. In this work, the dynamic model is developed using a computationally efficient method: Discrete Time Transfer Matrix Method (DT-TMM). The concepts and principle of DT-TMM are briefly overviewed, and then are applied to a mobile flexible robot arm for dynamic modeling with the detailed procedure. Numerical simulations and dynamic analyses are performed to illustrate the effectiveness of the proposed dynamic modeling method, and to provide the clues for our ongoing research work in the design and control of mobile robot manipulators.