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The silylated multidentate phenoxyphosphine ligands bis(trimethylsilyloxyphenyl)phenylphosphine and tris(trimethylsilyloxyphenyl)phosphine were observed to readily react with Re(O)(X)Cl2(PPh3)2 (X = Cl or OEt). This occurred through the elimination of the chloro or ethoxy substituents and the replacement of one initially coordinated triphenylphosphine by the phosphorus center of the multidentate ligand.

A method of preparation for the soluble and insoluble alkali metal derivatives of the Ph4P2N4S2 dianion is the reduction of 1,5-Ph4P2N4S2 by M(BEt3H) in THF. These alkali metal derivatives can be used in the synthesis of organic derivatives and the metal complexes of the P2N4S2 ring. Ph4P2N4S2 dianion is a very strong reducing agent. The lithium and sodium derivatives of the dianion are insoluble, yellow powders. The bonding mode of the ligands are automatically adjusted to satisfy the electronic demands of transition metals.

Multinuclear NMR spectroscopy helps characterize lithium iodide adducts, prepared by a reaction of organic iodides with lithium reagents. These adducts upon dissolution in CH2Cl2 produce eight-membered rings with boat conformation. Heating leads to the formation of chair conformers from boat conformers. Synthesis of N-methylated adduct involves the reaction of methyl triflate with Ph4P2N4(SPh)2.

Aseries of hydrido, alkyl, alkenyl and related heterobimetallic complexes of Rh and Os have a sigma-bound organic group on each metal. The methyl hydride species, on being subject to site-specific reductive elimination, yield an unstable and unsaturated Os center, followed by orthometallation of the dppm phenyl rings to form a saturated Os2+ center. X-ray crystallographic studies of two of the complexes reveal the presence of three carbonyl groups on Os and the terminal binding of a cyanomethyl or methyl group to Rh.

Metallocene dihalides MCp2Cl2 (M = Ti, Zr, Hf) react with (Li(Ph4P2N4S2R)THF)2 (R = Me, tBu, Ph, CH2PPh2) to produce complexes of the type MCp2Cl(Ph4P2N4S2R). X-ray analysis shows an eta(super 2)-N,S type of bonding of the (Ph4P2N4S2R)(super -) anion to the metal. This type of zirconium complex reacts with various electrophiles to produce regiospecific functionalized P2N4S2 ring. Spectroscopic techniques and x-ray analysis show this complex as a hydrogen-bonded dimer.

Studies of step-shaped dimers, (Li(Ph4P2N4S2R).THF)2, using 7Li and 31P NMR techniques reveals their fluxional nature. The reaction of the dimer with cis- or trans-MCl2(PEt3)2, where M = Pt, Pd, results in trans-structures with the Ph4P2N4S2R anion's sulfur atom attached to the metal. This involves M-S bond rotation with activation energies ranging from 41 to 46 kJ per mol.

The 31P and 77Se nuclear magnetic resonance spectra characterize the reaction of 1,5-Ph4P2N4Se2 with Pt(PPh3)2(CH2 double bonded with CH2) or Pd(PPh3)4 in toluene at zero degrees centigrade by the production of eta2-Se,Se'-bonded complexes of M(PPh3)(1,5-Ph4P2N4Se2)(2a, MPt; 2b, MPd). Detailed coupling information for the 2a and 2b is obtained from the 77Se nuclear magnetic resonance spectra simulation. The corresponding eta2-Se, N-mu, eta1-Se' bonded dimers are produced by heating 2a or 2b in boiling toluene.

The reaction of the diphosphadithiatetrazocines 1,5-E24N4S2, where R = Me, Et and Ph and E = PR2 and CNMe2, and the trithiatetrazocine PhCN3S3CNPPh3 with (PtCl2(PEt3))2 in a polar solvent results in 1:1 adducts containing a heterocyclic ligand bound to a platinum by an endocyclic nitrogen atom. These adducts have weak Pt-N bonds, as suggested by the facile replacement of the heterocyclic ligands by THF.

The reactions of the bis(phosphine chalcogenides) CH2(PXR2)(PYR'2), where X and Y = O, S and Se, and their anions (CHPXR2)(PYR'2)1- with chloroplatinum complexes (PtCl4)2-, Pt2Cl4(PEt3)2 or (Pt2Cl2 PEt3 4)2+ produce coordination complexes. These exhibit at least five different coordination modes. The neutral ligands and the anionic ligands with X = Y = S show an X,Y coordination. The anions in a strained four-member ring exhibit a C,X coordination. A monodentate C coordination of the anions and a complex C,S bridging mode involving a dianionic ligand and two metal centers were also exhibited.

Compound‐specific carbon isotope analysis (δ13C) of meteoritic organic compounds can be used to elucidate the abiotic chemical reactions involved in their synthesis. The soluble organic content of the Murchison carbonaceous chondrite has been extensively investigated over the years, with a focus on the origins of amino acids and the potential role of Strecker‐cyanohydrin synthesis in the early solar system. Previous δ13C investigations have targeted α‐amino acid and α‐hydroxy acid Strecker products and reactant HCN; however, δ13C values for meteoritic aldehydes and ketones (Strecker precursors) have not yet been reported. As such, the distribution of aldehydes and ketones in the cosmos and their role in prebiotic reactions have not been fully investigated. Here, we have applied an optimized O‐(2,3,4,5,6‐pentafluorobenzyl)hydroxylamine (PFBHA) derivatization procedure to the extraction, identification, and δ13C analysis of carbonyl compounds in the Murchison meteorite. A suite of aldehydes and ketones, dominated by acetaldehyde, propionaldehyde, and acetone, were detected in the sample. δ13C values, ranging from −10.0‰ to +66.4‰, were more 13C‐depleted than would be expected for aldehydes and ketones derived from the interstellar medium, based on interstellar 12C/13C ratios. These relatively 13C‐depleted values suggest that chemical processes taking place in asteroid parent bodies (e.g., oxidation of the IOM) may provide a secondary source of aldehydes and ketones in the solar system. Comparisons between δ13C compositions of meteoritic aldehydes and ketones and other organic compound classes were used to evaluate potential structural relationships and associated reactions, including Strecker synthesis and alteration‐driven chemical pathways. [ABSTRACT FROM AUTHOR]

A zirconyl complex of the P2N4S2 unsaturated ring with an eta(super 2)-N,S bonding mode is synthesized by the reaction of a dilithio compound R = t(Bu) with 2 equivalents of Cp2ZrCl2 in THF at 0 degrees Centigrade. Eta(super 2)-N,S bonding of the Ph4P2N4S2But anion enables reaction with electrophiles.

The complex 1,5-Ph4P2N4S2 reacted with Li(Et3BH) in tetrahydrofuran to generate the corresponding dianion. The dianion reacted with diiodomethane to yield the bicyclic compound Ph4P2N4S2CH2 which possesses a methylene group bridging the sulfur atoms of the P2N4S2 ring. Deprotonation of the bicyclic compound resulted in the carbanion Ph4P2N4S2CHLi which, when reacted with iodomethane, gave Ph4P2N4S2CH(CH3).