Low coordinate hypervalent phosphorus

Abstract

A. Complexes with the Transition Group 6 1230 Metals, Cr and W B. Complexes with the Transition Group 7 1230 Metal, Mn C. Complexes with the Transition Group 8 1231 Metals, Fe and Ru D. Complexes with the Transition Group 10 1232 Metals, Ni, Pd, and Pt E. Complexes with the Transition Group 11 1234 Metal, Ag X. Conclusions 1235 XI. Abbreviations 1236 XII. References 1236 I. Introduction This review marks 10 years of research into the chemistry of low-coordinate hypervalent phosphorus compounds.1 The first tricoordinated hypervalent phosphorus compound, 10-P-323,7-di(tert-butyl)-5-aza-2,8dioxa-l-phosphabicyclo[3.3.0]octa-2I4,6-triene (AD-PO),3 was reported in 1983.4 Another type of 10-P-3 intermediate, 1, was discovered by Schmid peter and Lochschmidt in this same time frame.5 The work by Schmidpeter et al. and Arduengo et al. represent two different ligand designs to stabilize the 11n memory of Linus Amadeus and Schroeder. * Contribution no. 6745 from DuPont Science and Engineering Laboratory. * DuPont. I Himont. Anthony J. Arduengo, III (b 1952) was raised In Atlanta, GA. He received the Bachelor of Science degree (with honor) in chemistry from The Georgia Institute of Technology (1974) and Ph.D. in organic chemistry from the same Institution in 1976. After a year In Industry with DuPont's Central Research Department, he joined the organic chemistry faculty of The University of Illinois-Urbana. In 1984 he returned to DuPont where he has held various positions and Is currently a Research Leader in the Polymer Science Section of the Central Science and Engineering Laboratory. He has served on the editorial boards of Chemical Reviews and Heteroatom Chemistry as well as the IUPAC commission on Inorganic nomenclature. His research interests are broadly in the area of main group element chemistry with particular interest in compounds with unusual valence. Hobbies include trumpet playing, bicycling, antique cars, and classical music. Constantine A. Stewart was born in 1957 in San Angelo, TX. He received his Bachelor of Arts in chemistry (1980) from Texas Tech University in Lubbock, TX, and his Ph.D. in inorganic chemistry from the University of Texas at Austin (1984). He spent two years as a Visiting Research Scientist at Central Research and Development at DuPont. In 1986 he joined Himont U.S.A., Research and Development. He is currently working In the field of Ziegler-Natta catalysis. His hobbies include bicycling and photography.T-shaped 10-P-3 geometry. Both designs employ a bicyclic five-membered ring effect to stabilize an axialequatorial-axial chelation of the central pseudo-trigonal

Why edge inversion? Theoretical characterization of the bonding in the transition states for inversion in F n NH(3−n) and FnPH(3−n) (n = 0–3)

“…Factors that stabilize the T-shaped structures of these compounds include electronegative ligands (facilitating the formation of the recoupled pair bond dyad) and conjugated p system (allowing delocalization into the space usually occupied by the lone pair). Such compounds are expected to be widespread; their chemistry has been reviewed in detail by Arduengo and Stewart [2].…”

“…In this section, we take a step back to examine the triatomic molecules, because recoupled pair bond dyads also exist in NH 2 P state that contains a 3s-recoupled pair bond dyad, and relaxes to a bent geometry upon geometry optimization, incorporating additional 3p character into the P bonding orbitals. So let us compare the recoupled pair bond dyad in the 2 P and 2 A 1 states of PH 2 with the bonds in the PH 3 and FPH 2 transition states to understand how the s-recoupled pair bond dyad evolves in these species.…”

“…Investigations of the T-shaped pnictogen transition states for inversion were inspired by the experimental synthesis of the first molecule containing a T-shaped, tricoordinated hypervalent phosphorous structure, 5-aza-2,8-dioxa-3,7-di-tert-butyl-l-phosphabicyclo [3.3.0]octa-3,6-diene (ADPO) [1,2]. Another hypervalent 10-P-3 compound, an intermediate, was discovered by Lochschmidt and Schmidpeter at approximately the same time [3].…”

The synthesis, characterization and biological evaluation of a stable phosphorus ylide and an imidazole as novel compounds

“…Phosphonium salts can also prepared by Michael addition of phosphine to activated olefins. Michael addition of phosphorus(III) compounds such as triphenylphosphine to acetylenic esters leads to reactive 1,3-dipolar intermediate betaines which are not detected even at low temperature [4,19,20].…”

Triphenylphosphite as a good reagent for the diasteroselective synthesis of phosphonate esters

“…[1][2][3][4][20][21][22] The successful attack by nucleophilic trivalent phosphorus on a carbon atom is facilitated when the latter is part of, or conjugated with, a carbonyl group, or when it is part of an unsaturated bond otherwise activated. [2][3][4][5][6][7][8][9][10] There are many studies on the reaction between trivalent phosphorus nucleophiles and α, β-unsaturated carbonyl compounds in the presence of a proton source such as an alcohol or a phenol. 2,10,11 New or improved methods for phosphonate synthesis continue to attract much attention because phosphonates have biologically important properties and serve as natural products, analogues of phosphates, phosphonopeptides, amino acid analogues and pro drugs.…”