How Not to Discover a New Reagent. The Evolution and Chemistry of Woollins' Reagent

The pathways in research can be complex. This review provides a personal account of the winding scientific and funding road that led to Woollins' reagent. The synthesis and applications of Woollins' reagent are summarised.PostprintPeer reviewe

Organophosphorus-tellurium chemistry : from fundamentals to applications

T.C. thanks the NSERC (Canada) for continuing funding. J.D.W. is grateful to the University of St Andrews for support. A.N. thanks the EPSRC for financial support.PostprintPeer reviewe

cis-Dichloridobis(triisopropoxy­phosphine)­platinum(II)

The title compound, [PtCl2(C9H21O3P)2], was obtained from a solution of PtCl2(COD) (COD = 1,5-cyclooctadiene) and triisopropyl­phosphite in dichloro­methane. The complex features a Pt(II) atom coordinated by two Cl and two P atoms, yielding a slightly distorted cis square-planar geometry

2,2′-o-Phenyl­enediacetonitrile

In the title compound, NCCH2C6H4CH2CN, the bond lengths and angles are within normal ranges. The benzene ring makes dihedral angles of 4.94 (8) and 77.04 (8)° with the C—C—C—N mean planes. Weak non-conventional C—H⋯N hydrogen bonds are effective in the stabilization of the crystal structure. The weak C—H⋯N contacts form anti­parallel chains running in the a + c direction, and ring systems with two N-atom acceptors and four H-atom donors

Bis(phenyl­phospho­nic) anhydride

The asymmetric unit of the title compound, C12H12O5P2, contains four independent mol­ecules, generating two dimers via pairs of inter­molecular O—H⋯O hydrogen bonds, forming R 2 2(8) rings. The two aryl rings of each mol­ecule form dihedral angles of 108.6 (1), 103.2 (1), 12.5 (2) and 8.1 (2)° in the four mol­ecules

Varying the flexibility of the aromatic backbone in half sandwich rhodium(III) dithiolato complexes : a synthetic, spectroscopic and structural investigation

A series of rhodium(III) half sandwich complexes of the type [Cp*Rh(PMe3)(S—R—S)]; S—R—S = naphthalene-1,8-dithiolate, acenaphthene-5,6-dithiolate, [1,1′-biphenyl]-2,2′-dithiolate and [2,2′-binaphthalene]-1,1′-dithiolate are reported. In the case of [2,2′-binaphthalene]-1,1′-dithiolate this represents an infrequent example of a metal complex containing this ligand. All the complexes have been fully characterised using multinuclear NMR spectroscopy and single crystal X-ray diffraction. The single crystal X-ray structure of the starting material [Cp*Rh(PMe3)Br2] ( 1 ) is also reported for the first time.Publisher PDFPeer reviewe

Synthesis and structural study of novel selenation derivatives of N, N-Dialkylcyanamides

We are grateful to the University of St Andrews for financial support and the EPSRC National Mass Spectrometry Service Centre (Swansea) for mass spectral measurements.The reaction of 2,4-bis(phenyl)-1,3-diselenadiphosphetane-2,4-diselenide {[PhP(Se)(µ-Se)]2, Woollins’ reagent, WR } with N, N-dialkylcyanamides 1–3 in refluxing toluene solution led to the corresponding [2+3] cycloaddition products 4-dialkylamino-2,5-diphenyl-1,3,2,5-selenazadiphosphole 2,5-diselenides 4–6 in good yields, the latter were further treated with water resulting in the corresponding hydrolysis derivatives dialkyl-selenoureas 7–9 , and phosphinodiselenoates 10 and 11 . Selenourea 7 could be transferred into 1,3-selenazol-2-amines 12–15 in excellent yields by further cyclization with four different α-haloketones. All new compounds have been characterized by IR spectroscopy, multi-NMR (1H, 13C, 31P, 77Se) spectroscopy and accurate mass measurement. The single crystal X-ray structural features of nine new compounds are also discussed.PostprintPostprintPeer reviewe

Organo phosphorus-sulfur-nitrogen heterocycles from thionation of Schiff bases

Funding: University of St Andrews.A series of heteroatom derivatives were prepared from the reactions of amido-Schiff bases as well as simpler imine with 2,4-diferrocenyl-1,3,2,4-diathiadiphosphetane 2,4-disulfide ( FcLR ). Six related structures have been characterized by single crystal X-ray diffraction.Publisher PDFPeer reviewe

Application of four-membered ring chalcogenation reagents to the synthesis of new phosphorus-chalcogen heterocycles

The authors are grateful to the University of St Andrews for financial support.The reaction of four-membered ring chalcogenation reagents such as Lawesson’s reagent, 2,4-diferrocenyl-1,3,2,4-diathiadiphosphetane 2,4-disulfide (the ferrocene analogy of Lawesson’s reagent) and Woollins’ reagent with alkyl- or aryl-dithiols in refluxing toluene gave a series of five- to seven-membered organo-phosphorus-chalcogen heterocycles in 24% to 87% yields. Five representative X-ray structures confirm the formation of these five- to seven-membered heterocycles.Publisher PDFPeer reviewe

Novel five- and six-membered ring phosphorus-selenium heterocycles from selenation of amido-Schiff bases

Authors are grateful to the University of St Andrews for financial support.Woollins’ reagent, [2,4-bis(phenyl)-1,3-diselenadiphosphetane-2,4-diselenide], serving as a selenating-reductive cycloaddition reagent, reacts with nonconjugated amido-Schiff bases to give the corresponding six-membered 1,3,4-selenadiazoles via a ring-expansion accompanied by an additional selenation/cyclization to the imine bond and C═O group; meanwhile, under the same reaction conditions, the selenation of conjugated amido-Schiff bases leads to a series of fused heterocycles with two five-membered rings. Eight single-crystal X-ray structures confirming the formation of these five- and six-membered heterocycles are discussed.Publisher PDFPeer reviewe