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Sustainable technology for constructing Pd-catalyzed C–N bonds involving aliphatic amines is reported. A catalytic system that relies on low levels of recyclable precious metal, a known and commercially available ligand, and a recyclable aqueous mediumare combined, leading to a newly developed procedure. This new technology can be used in ocean water with equal effectiveness. Applications involving highly challenging reaction partners constituting late-stage functionalization are documented, as is a short but efficient synthesis of the drug naftopidil. Comparisons with existing aminations highlight the many advances being offered.

Recent advances of high power and narrow bandwidth laser diodes emitting at 1.9 m open the path to direct diode pumping of Ho3+:YAG lasers. The usual method to pump such laser is to use thulium fiber laser which has an excellent beam quality with high power and narrow bandwidth emission. The draw back of this system is the low efficiency of this fiber laser and the increased overall complexity. In this paper we present first results of resonantly diode pumping of a Ho3+:YAG laser with fiberlike geometry. The fiber coupled diode modules used for pumping in this work (BrightLockTMUltra-500) produce each 25 W at 1.91 m with 3 nm linewidth. The fiber has a core diameter of 600 m with 0.22 numerical aperture. The Ho3+:YAG crystal has a diameter of 1.2 mm, a length of 60 mm, a doping concentration of 0.75 at.% and is symmetrically pumped by two diode modules from both ends. Total internal reflection on the polished rod barrel allows a high pump intensity along the rod length. The Ho3+:YAG laser cavity is composed of a high reflective flat mirror and a concave output coupler with a radius of curvature of 500 mm. With an output coupler of 50 % we measured a threshold of 11 W. The maximum output power was 11.87 W with a wavelength of 2.09 m. The incident power to output power slope efficiency was 0.38 at currently 4 % of internal losses.

The article discusses the capability of wavelength stabilization technology for high-power laser diodes to bring an efficient spectral width that is locked over a wide temperature range. It notes that laser diodes are by a wide margin unsurpassed as efficient sources of radiation and have carved out dominant positions in many laser applications. The author points out that laser applications such as fiber-optic telecommunications and optical data storage would not exist at all without the diode.