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Abstract Hydrophosphination using calcium compounds as catalysts under irradiation is described as a foray into s‐block photocatalysis. Transition‐metal compounds have been highly successful hydrophosphination catalysts under photochemical conditions, utilizing substrates previously considered inaccessible. A calcium hydrophosphination precatalyst, Ca(nacnac) (THF) (N(SiMe₃)₂) (1, nacnac = HC[(C(Me)N‐2,6‐ⁱPr₂C₆H₃)]₂), reported by Barrett and Hill, as well as the presumed intermediate, Ca(nacnac) (THF) (PPh₂) (2), and the Schlenk equilibrium product, Ca[N(SiMe₃)₂]₂(THF)₂(3) were screened under photochemical conditions with a range of unsaturated substrates including styrenic alkenes, Michael acceptors, and dienes with modest to excellent conversions, though unactivated alkenes were inaccessible. All compounds exhibit enhanced catalysis under irradiation by light emitting diode (LED)‐generated blue light. Nacnac‐supported compounds generate radicals as evidenced by Electron Paramagnetic Resonance (EPR) spectroscopy and radical trapping reactions, whereas unsupported calcium compounds are EPR silent and appear to undergo hydrophosphination akin to thermal reactions with these compounds. These results buttress the notion that photoactivation of π‐basic ligands is a broad phenomenon, extending beyond the d‐block, but like d‐block metals, consideration of ancillary ligands is essential to avoid radical reactivity. 

Abstract Pressure is mounting to minimize the carbon footprint of chemical industry while increasing its sustainability. An argument is made that working from Green Chemistry principles during discovery‐based catalysis results in effective chemistry and circumvents a need to “rediscover” chemical reactivity under sustainable conditions. Examples of comparative success in selected examples of hydrophosphination catalysis in various degrees of development are provided to support two main ideas: 1) Starting from more sustainable practices in chemical discovery is inertia in methodology that should be overcome, and 2) substantial challenges remain in catalysis for which sustainable solutions would positively impact other areas of chemistry. Examples of successes, even in the face of the challenges noted, are presented herein as indications that even as a starting point, sustainability can meet short‐ and long‐term needs. These ideas indicate critical but simple strategies for fundamental research to be impactful in the sustainability of the chemical industry broadly. 

Abstract Group I alkoxides are highly active precatalysts in the heterodehydrocoupling of silanes and amines to afford aminosilane products. The broadly soluble and commercially available KO^tAmyl was utilized as the benchmark precatalyst for this transformation. Challenging substrates such as anilines were found to readily couple primary, secondary, and tertiary silanes in high conversions (>90 %) after only 2 h at 40 °C. Traditionally challenging silanes such as Ph₃SiH were also easily coupled to simple primary and secondary amines under mild conditions, with reactivity that rivals many rare earth and transition‐metal catalysts for this transformation. Preliminary evidence suggests the formation of hypercoordinated intermediates, but radicals were detected under catalytic conditions, indicating a mechanism that is rare for Si−N bond formation. 

Abstract Hydrophosphination activity has been solicited from the parent and decamethyl zirconocene dichloride compounds, Cp₂ZrCl₂and Cp*₂ZrCl₂. Given recent reports of photocatalytic hydrophosphination, these compounds were irradiated in the near ultraviolet (UV) as precatalysts resulting in the successful hydrophosphination of styrene substrates and activated alkenes. Irradiation appears to induce homolysis of the Cp or Cp* ligand, resulting in radical hydrophosphination. Successful detection of this radical reactivity was achieved by monitoring for EPR signals within situirradiation, a methodology proving to be general for the determination of radical versus closed‐shell reactivity in transition‐metal photocatalysis. 

Abstract Organophosphines have garnered attention from many avenues ranging from agriculture to fine chemicals. One‐time use of phosphate resources has made sustainable use of phosphorus overall imperative. Hydrophosphination serves as an efficient method to selectively prepare P−C bonds, furnishing a range of phosphorus‐containing molecules while maximizing the efficient use of phosphorus. Since the first report in 1958, a wide array of catalysts have appeared for hydrophosphination, a reaction that is spontaneous in some instances. This review presents a representative view of the literature based on known catalysts through mid‐2022, highlighting extensions to unique substrates and advances in selectivity. While several excellent reviews have appeared for aspects of this transformation, this review is meant as a comprehensive guide to reported catalysts. 

Grignard reagents are simple, accessible catalysts for the dehydrocoupling of amines and silanes that increases selectivity of these reactions over other commercially available catalysts for Si–N bond formation. 

The titanium amidate compound bis(N-tert-butylacetamido)(dimethylamido)(chloro)titanium was synthesized by the protonolysis of tris(dimethylamido)(chloro)titanium and structurally characterized by 1H and 13C NMR spectroscopy as well as X-ray diffraction. The compound does not appear to react cleanly nor readily with routine alkylating agents such as sec-butyllithium, benzyl potassium, or trimethylsilyl methyllithium. 

A family of commercially available organolithium compounds were found to effectively catalyze the heterodehydrocoupling of silanes and amines under ambient conditions. 

2-(((2,7-Dihydroxynaphthalen-1-yl)methylene)amino)-3′,6′-bis(ethylamino)-2′,7′-dimethylspiro[isoindoline-1,9′-xanthen]-3-one was synthesized using Rhodamine 6G hydrazide (prepared using literature methods) and commercially available 2,7-dihydroxynaphthalene-1-carbaldehyde via imine condensation. Structural characterization was performed using FT-IR, 1H-NMR, 13C-NMR, X-ray, and HRMS. This Schiff base shows promise as a ligand for the colorimetric analysis of uranium in water.