(Morpholino)diphenylphosphine, unlike PPh3, gives only two new compounds, (OC4H8N)Ph2PNS3N3, (1), and 1,5-[(OC4H8N)Ph2PN]2S 4N4, (2), on reacting with S4N4. The reaction temperature, solvent, and mole ratio of the reactants are critically important in their synthesis. For the first a ring contraction of compound (2) to compound (1) in solution at room temperature has been observed and evidence for the elimination of the 'NSR' group (R = phosphinimino group) obtained.

Colacot J. Thomas

IIT Madras is a public technical and research university located in Chennai, Tamil Nadu. Founded in 1959, it is recognised as an Institute of National Importance.

IIT Madras has been ranked as the top engineering institute in India for four years in a row by the National Institutional Ranking Framework of the MHRD

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IIT Madras

Cyclic sulphur–nitrogen compounds and phosphorus reagents. Part 2. Reactions of tetrasulphur tetranitride with (morpholino)diphenylphosphine. First observation of the ring contraction of 1,5-[(OC4H8N)Ph2PN]2S4N4 to (OC4H8N)Ph2PNS3N3 in solution

Journal of the Chemical Society, Dalton Transactions

Electrochemical (polarographic, cyclic voltammetric, and coulometric) and coordination behaviour of several symmetrically and unsymmetrically substituted phosphiniminocyclotrithiazenes have been studied. Polarograms of R3PN-S3N3 R = C6H5, p-ClC6H4, p-H3CC6H4, and (OC4H8N)), Ph2OC4H8N)PN-S3N3, and Ph(OC4H8N)2PN-S3N3 give two cathodic waves. Cyclic voltammograms of Ph3PN-S3N3 (1) and (OC4H8N)3PN-S3N3 (2) reveal nearly the same oxidation peak potential but different reduction potentials. Controlled potential electrolysis of 1 and 2 at +0.6 V indicates exocyclic cleavage and ring degradation. Cathodic reduction behaviour of Ph3PN-S3N3 suggests the possibility for the) formation of 1,5-(Ph)3(PN)2S4N4 under electrochemical conditions. Reaction of nickel chloride hexahydrate with heterocycle 1 in 1:2 molar ratio in acetonitrile affords the complex, ([NiS2N2H2] (A) (90% yield) and [Ph3PNH2]Cl salt as products. Analogous reactions with other ligands of this type (two symmetrical (sym.) and three unsymmetrical (unsym.)) except 2 also give A, while ligand 2 reacts with anhyd NiCl2 in an equimolar ratio to afford a dark green, square-planar complex ((OC4H8N)3(PN-S3(N·NiCl 2 (B)) whose ESCA results assist in providing its coordination details. The study reveals a high tendency of these heterocycles to different types of ring cleavage.

Canadian Journal of Chemistry

Studies on electrochemical and coordination behaviour of phosphiniminocyclotrithiazenes

The reactions of S4N4 with phosphines of the type PhPR2 (1-5) and PhR′PR [6-11 (R′ = dicyclohexylamino), R: 1,6 = pyrrolidino; 2,7 = piperidino; 3,8 = morpholino; 4,9 = N-methylpiperazino; 5,10 = hexamethylenimino; and 11 = anilino] afford the phosphiniminocyclotrithiazene derivatives, 12-22 at room temperature. Only in the case of the phosphine 10 was the disubstituted derivative 23 isolated (in 65% yield). The trithiazene derivatives of the chiral phosphines in refluxing CH3CN produce the acyclic compounds → PN-S3N, 24-27 in ca. 60% yield. Norbornadiene reacts at room temperature with the cyclotrithiazene derivatives to give the addition products 28-35. → P=N-S3N3 derivatives are found to be stable in 2M NaOH. © 1997 John Wiley &amp; Sons, Inc.

Heteroatom Chemistry

Reactions of S4N4 with tertiary phosphines - Synthesis of phosphiniminocyclothiazenes and their reactions

Tetrasulfurtetranitride, S4N4 reacts with (2‐pyridylamino)‐diphenylphosphine in MeCN at room temperature to form the cyclotrithiazene (NC5H4NH)‐Ph2PNS3N3 (1) in good yield. By contrast, the cyclophosphathiazenes Ph2PS2N3 (2) and 1,5(Ph2P)2S2N4 (3) are isolated from the same reaction mixture under reflux conditions. In solution, compound 1 is found to be transformed into 2. The reaction of S4N4 with (2‐pyridylamino)phenyl(dicyclohexylamino)phosphine in MeCN at room temperature affords Ph(DCA)PS2N3 (4) (DCA = dicylohexylamino) as the only reaction product. This on treatment with norbornadiene produces the addition product Ph(DCA)PS2N3·C7H8 ( 5 ). The structure of 4 has been established by X‐ray diffraction. Its PSN ring adopts a skew boat conformation with SN bond lengths varying from 1.574(4) to 1.606(4) Å. The mean value of the endocyclic PN bonds amounts to 1.618(3) Å. Copyright © 1994 VCH Publishers, Inc.

Cyclic sulfur nitrogen compounds and phosphorus reagents: Part XII. Reactions of S4N4 with (2‐pyridylamino) phosphines [1]

Reactions of S4N4 with diphosphines, Ph2P(X)PPh2 (X = NC4H8N, CH2CH2) have resulted in the isolation of N3S3NPPh2(X)Ph2PNS3N3 (X = NC4H8N, CH2CH2), (S)PPh2(CH2CH2)Ph2PNS3N3, and (S)PPh2NC4H8NPh2P(S) as new compounds. These heterocycles have been characterized by analytical and spectroscopic (IR, UV‐VIS, 1H and 31P‐NMR, and MS) techniques. Copyright © 1993 Verlag GmbH &amp; Co. KGaA, Weinheim

ZAAC ‐ Journal of Inorganic and General Chemistry

Reactions of S4N4 with diphosphines, Ph2P(X)PPh2 (X = NC4H8N, CH2CH2)

Room temperature reactions of S4N4 with (amino) diphenylphosphines, (R)Ph2P, have basically yielded two different types of SN heterocycles under two different stoichiometric conditions. Phosphiniminocyclotrithiatriazenes, (R)Ph2PNS3N3 (R = C4H8N, C5H10N, C6H12N, CH3NC4H8N, (C6H11)2 N, and (C6H5CH2)2N) have been obtained (yield 45–76%) from a 1:2 mole ratio (S4N4:(R)Ph2P) reaction, while the disubstituted S4N4 derivatives, 1,5‐[Ph2(R)PN]2S4N4 (R = C4N8N, C5H10N, and C6H12N) have been obtained (yield 30–45%) only from a 1:3.5–4 mole ratio reaction. All the 1,5‐[Ph2(R)PN]2S4N4 derivatives prepared in this study undergo a room temperature solution phase transformation to the corresponding (R)Ph2PNS3N3 heterocycles. Copyright © 1992 VCH Publishers, Inc.

Cyclic SN compounds and phosphorus reagents: Part X. Synthesis and characterization of phosphinimino‐substituted SN heterocycles

Inorganic Syntheses

Tetrasulfur Tetranitride, S4N4

Inorganic Chemistry

A ring expansion reaction of (Me2NCN)(NSCl)2 with Me3SiNSO: preparation of the bicyclic compounds R2NCS3N5 (R = Me, Et, iso-Pr) and x-ray crystal structure of the folded eight-membered ring 1,5-Me2NC(NSN)2SCl

Chemical Reviews

Synthetic methods and structure-reactivity relationships in electron-rich sulfur-nitrogen rings and cages

Reactions of tetrasulfur tetranitride with chlorodiphenylphosphine, dichlorophenylphosphine, and phosphorus trichloride: preparation of the six-membered rings (Ph2PN)2(NSX) (X = Cl, Br, I, Ph, NR2) and the related cation [(Ph2PN)2NS]+

ACS Symposium Series Rings, Clusters, and Polymers of the Main Group Elements

Cyclophosphathiazenes Containing Two- or Three-Coordinate Sulfur

Cyclic sulphur-nitrogen compounds and phosphorus reagents. Part 2. Reactions of tetrasulphur tetranitride with (morpholino)diphenylphosphine. First observation of the ring contraction of 1,5-[(OC4H8N)Ph2PN]2S 4N4 to (OC4H8N)Ph2PNS3N3 in solution

Journal	Journal of the Chemical Society, Dalton Transactions
ISSN	14727773
Open Access	No