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

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

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

Single crystal X-ray structural features of aromatic compounds having a pentafluorosulfuranyl (SF5) functional group

The authors are grateful to the University of St Andrews for financial support.Nine pentafluorosulfuranyl (SF5)-containing aromatic compounds have been characterized crystallographically. The SF5 group has an umbrella geometry, and the sulfur atom in the SF5 group is in an approximately octahedral coordination environment. All S-F bond lengths [1.572(3) to 1.618(3) Å] are very similar and the C-S-Fax bond angles [178.94(14) to 180°] are very close to each other. The angle of two adjacent Feq is approximate to 90°. The intramolecular and intermolecular interactions such as Caryl-H···Feq, Caryl-H···O/N/F/Cl interactions, and π-stacking interactions play a very important role in their three-dimension packing frameworks.PostprintPostprintPeer reviewe

Phosphorus-sulfur heterocycles incorporating an O-P(S)-O or O-P(S)-S-S-P(S)-O scaffold : one-pot synthesis and crystal structure study

The authors are grateful to the University of St Andrews for financial support.A new one-pot preparative route was developed to synthesize novel organophosphorus sulfur heterocycles via the reaction of the four-membered ring thionation reagent [2,4-diferrocenyl 1,3,2,4-diathiadiphosphetane 2,4-disulfide (FcLR, a ferrocene analogue of Lawesson’s reagent)] and alkenyl/aryl-diols and I2 (or SOCl2) in the presence of triethylamine. Therefore, a series of five- to ten-membered heterocycles bearing an O-P(S)-O or an O-P(S)-S-S-P(S)-O linkage were synthesized. The synthesis features a novel application of the multicomponent reaction, providing an efficient and environmentally benign method for the preparation of the unusual phosphorus-sulfur heterocycles. Seven representative X-ray structures confirm the formation of these heterocycles.Publisher PDFPeer reviewe

Bis(furan-2-ylcarbon­yl) diselenide

The title mol­ecule, C10H6O4Se2, lies on a twofold rotation axis. The Se—Se bond length of 2.305 (3) Å is similar to that in diphenyl diselenide [2.3066 (7) and 2.3073 (10) Å for the P and M isomers, respectively] and longer than that in 1,8-diseleno­naph­thalene [2.0879 (8) Å]. The mol­ecule adopts a gauche conformation with respect to the C=O groups

1,2-Bis(2-bromo­benz­yl)diselane

In the title compound, C14H12Br2Se2, the Se—Se bond length [2.3034 (9) Å] is similar to those in diphenyl diselenide [2.3066 (7) and 2.3073 (10) Å] and shorter than that in 1,8-diselenona­phthalene [2.0879 (8)Å]. The mol­ecule adopts a classical gauche conformation

5-Benzyl­idene-2,3-diphenyl-1,2-selenaphosphole-2-selenide

The title compound, C23H19PSe2, has a central five-membered twist C3PSe ring conformation. One phenyl ring substituent, attached to an sp 2 carbon, is approximately coplanar with the C3PSe ring whilst the other organic substituents, attached to an sp 3-carbon and a PV atom, lie on the same side of the ring

2-Phenyl-5-(p-tol­yl)-1,3,4-oxadiazole

The title compound, C15H12N2O, adopts the expected near-planar geometry, the phenyl and tolyl rings being inclined relative to the oxadiazole ring by 3.8 (3) and 8.3 (2)°, respectively. This allows adjacent mol­ecules to pack in a parallel fashion and form stacking along [010] via π–π inter­actions [centroid–centroid distances = 3.629 (2) and 3.723 (2) Å]. Further inter­molecular inter­actions include C—H⋯π inter­actions and weak C—H⋯N hydrogen bonds, giving rise to a crossed herringbone packing motif