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A new method for the synthesis of a-branched amines by reductive functionalization of tertiary carboxamides and lactams is described. The process relies on the efficient and controlled reduction of tertiary amides by a sodium hydride/ sodium iodide composite, in situ treatment of the resulting anionic hemiaminal with trimethylsilyl chloride and subsequent coupling with nucleophilic reagents including Grignard reagents and tetrabutylammonium cyanide. The new method exhibits broad functional-group compatibility, operates under transition-metal-free reaction conditions, and is suitable for various synthetic applications on both sub-millimole and on multigram scales. Recently, the Chiba group disclosed a controlled hydride reduction of tertiary carboxamides for the synthesis of aldehydes using a combination of NaH and NaI in THF. [15] Key to the success of this chemistry was the stability (prior to aqueous work-up) of the anionic hemiaminal intermediates formed through single hydride transfer from the activated NaH to the carboxamides. [16] Building on this discovery, we Scheme 1. Selected a-branched amines currently used in the clinic.

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First hand: The first example of a palladium-catalyzed asymmetric hydrogenation of α-acyloxy ketones (1) was accomplished to give the hydrogenated products 2 with by far the highest catalytic efficiency in up to quantitative conversions and excellent enantioselectivities. The hydrogenated products could serve as important intermediates for the preparation of many drug candidates. TFE=2,2,2-trifluoroethanol.

Flexible strain sensors are of great interest for future applications in the next-generation wearable electronic devices. However, most of the existing flexible sensors are based on synthetic polymer materials with limitations in biocompatibility and biodegradability, which may lead to potential environmental pollution. Here, we propose a naturally derived wearable strain sensor based on natural-sourced materials including milk protein fabric, natural rubber, tannic, and vitamin C. The obtained sensors exhibit remarkably enhanced mechanical properties and high sensitivity contrast to currently reported natural resource-based sensors, owing to the metal–ligand interface design and the construction of an organized three-dimensional conductive network, which well fit the requirements of electronic skin. This work represents an important advance toward the fabrication of naturally derived high-performance strain sensors and expanding possibilities in the design of environmental-friendly soft actuators, artificial muscle, and other wearable electronic devices.