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Dehydrocoupling is a unique reaction to p-block elements that allows for the formation of bonds between these main group elements with loss of hydrogen. The transformation is highly atom economical, and hydrogen is a relatively benign byproduct that also provides the thermodynamic driving force for the reaction. For these reactions, couplings between most of the p-block elements are known. In the instance when bonds between the same elements are formed, then this reaction primarily applies to elements in the third period (3p) and heavier. For reactions between different elements, most any combination of p-block elements is possible. These reactions are known to make small molecules and polymers. Catalysts for this reaction include metal compounds (i.e., organometallic catalysts), Lewis acids, and frustrated Lewis pairs, and the mechanisms of dehydrocoupling are highly varied, representing much of the spectrum of catalysis. 

An analysis of CHEM21 solvent categories reveals that green solvents are viable and often superior to oft-used toxic and hazardous solvents for catalytic hydrophosphination regardless of mechanism, substrate, or catalyst. 

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. 

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. 

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. 

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. 

Copper methoxide compound IPrCuOMe was unexpectedly formed in a reaction of IPrCuPPh2 with methyl acrylate. The alkoxide product was identified from the reaction mixture spectroscopically and structurally characterized. This C–O bond cleavage reaction likely depends on nucleophilicity of the Cu–P bond of IPrCuPPh2. 

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.