An examination of several catalytic reactions among the group 15 elements is presented. The connections between the chemistry of the pnictogens can sometimes be challenging, but aspects of metal–pnictogen reactivity...

A modular synthesis of tris(aryl)tren ligands has been demonstrated via the condensation of nitrilotracetyl chloride with different anilines followed by reduction. Varying the aniline in the condensation step from 2-methylthioaniline, to 2-phenylthioaniline, to 2-chloroaniline, generates 2,2',2"-nitrilotris(N-(2-(methylthio)phenyl)acetamide (1), 2,2',2"-nitrilotris(N-(2-(phenylthio)phenyl)acetamide (2) and 2,2',2"-nitrilotris(N-2-chlorophenyl)acetamide (3) respectively. The 2-chloroaniline synthesis is complicated by the production of N-(2chlorophenyl)-3,5-dioxo-1-piperazine-N-(2-chlorophenyl)acetamide (4), but can be adjusted to produce only 3. The reduction of complexes 1-3 proceeds with lithium aluminum hydride for 1 and 2 and with borane for 3 to yield the tris(aryl)tren ligands tris-(2-(2-(methylthio)phenylamino)ethyl)amine (5), tris-(2-(2-(phenylthio)phenylamino)ethyl)amine (6), and tris-(2-(2-chlorophenylamino)ethyl)amine (7). All three of these ligands can be deprotonated with tert-butyllithium for 5 and 7, and n-butyllithium for 6 to generate their trilithium complexes, 8, 9 and 10 for 5, 6 and 7 respectively, with 10 forming two different solvates (10a and 10b). All complexes are characterized by 1 H and 13 C NMR and the solid state structures of complexes 2, 3, 4, 7, 8, 9, 10a and 10b are described.

Hydrophosphination activity has been solicited from the parent and decamethyl zirconocene dichloride compounds, Cp2ZrCl2 and 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 with in situ irradiation, a methodology proving to be general for the determination of radical versus closed-shell reactivity in transition-metal photocatalysis.

Hydrophosphination activity has been solicited from the parent and decamethyl zirconocene dichloride compounds, Cp2ZrCl2 and 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 with in situ irradiation, a methodology proving to be general for the determination of radical versus closed-shell reactivity in transition-metal photocatalysis.

Hydrophosphination activity has been solicited from the parent and decamethyl zirconocene dichloride compounds, Cp2ZrCl2 and 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 with in situ irradiation, a methodology proving to be general for the determination of radical versus closed‐shell reactivity in transition‐metal photocatalysis.

Some Grenville-age rocks exposed in the uplifted region of the Hudson Highlands of southern New York are amphibole-dominant igneous rocks. The amphibole-rich rocks, which are locally pegmatitic in nature, are associated with magnetite ore and coarse-grained syenite; the ore was discovered and mined from the middle of the 18th century to the end of the 19th century. The amphiboles have attracted the attention of many researchers for nearly two centuries. Chemical analyses demonstrate that they are pargasite or hastingsite in composition and are particularly rich in Cl and K. High-precision crystal structure analyses of 11 Cl-rich amphiboles from the Hudson Highlands (0.0134 <R1 < 0.0169), including separation of M(1)Fe and M(1)Mg, allow corroboration of, and greatly extends the range of, previous models of Cl incorporation in amphiboles that were derived from a small number of samples. In addition to crystal structures and major-element analyses, trace-element data and Raman spectra are provided.

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