Reactions of (R)Ph2PNS3N3 heterocycles with olefins such as norbornadiene, norbornene and dicyclopentadiene have yielded different results. Like Ph3PNS3N3, (R)Ph2PNS3N3 (R = C4H8N, C5H10N, C6H12N, CH3NC4H8N and OC4H8N) compounds have given the cycloaddition products (R)Ph2PNS3N3 · C7H8 (yield 41 ‐ 62%) with norbornadiene, while norbornene and dicyclopentadiene have not produced the corresponding adducts under identical conditions. With Ph3PNS3N3 both norbornene and dicyclopentadiene have given the ring expanded heterocycle, 1,5‐[Ph3PN]2S4N4 in ca. 65% yield. The solution phase decomposition studies of (secondary amino) Ph2PNS3N3 derivatives have lead to the formation of (R)Ph2PNH2+X−, while (primary amino) Ph2PNS3N3 has given Ph2PS2N3 heterocycle in ca. 80% yield. Acid hydrolysis of (R)Ph2PNS3N3 derivatives has resulted in the isolation of Ph2P(O)OH in all the cases, where R is an amino group. Copyright © 1992 Verlag GmbH &amp; Co. KGaA, Weinheim

Colacot J. Thomas

Madhugiri N. Sudheendra Rao

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

It currently offers undergraduate, postgraduate and research degrees across 16 disciplines in Engineering, Sciences, Humanities and Management. About 596 faculty belonging to science and engineering departments and centres of the Institute are engaged in teaching, research and industrial consultancy.

IIT Madras

ZAAC ‐ Journal of Inorganic and General Chemistry

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

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

The reactions of the tertiary (amino)phosphines (R2N)3P [R2N = C4H8N-, C5H10N-, C6H12N-, OC4H8N-, and CH3NC4H8N-·] with S4N4 are described. The phosphiniminocyclotrithiazenes (R2N)3PN-S3N3 (1-5) are the only heterocyclic products isolated (60-80% yield). Excess (amino)phosphines cleave the heterocycles readily while norbornadiene reacts with them to give rise to the addition products, (R2N)3PN-S3N3·C7H8 (6-9) in small yields. The single crystal X-ray structure of (C5H10N)3PN-S3N3 (triclinic system, space group P1̄) gave the unit cell dimensions: a = 9.573(5), b = 10.372(6), c = 10.916(6) Å, α = 85.46(3), β = 81.13(4), γ = 79.73(4)°, V = 1052.25 Å3 and Z = 2. The structure has been compared with that of Ph3PN-S3N3 which is the only other compound of this type (R3PN-S3N3) whose X-ray structure is known. © 1990.

Polyhedron

Cyclic SN compounds and phosphorus reagents-VII. Reactions of S4N4 with tertiary (amino)phosphines: Synthesis and characterization of (R2N)3PN-S3N3 derivatives and their addition products with norbornadiene. X-ray crystal structure of (C5H10N)3PN-S3N3

Title full: Cyclic SN compounds and phosphorus reagents part 6. Reactions of S4N4 with symmetrical tertiary phosphines, R3P (R = t-C4H9, c-C6H11, C6H5CH2, p-MeOC6H4 and p-ClC6H4): Isolation and characterization of phosphinimino substituted cyclic sulphur nitrides. Unlike Ph3P, reactions of S4N4 with symmetrical tertiary phosphines, R3P (R = t-butyl, cyclohexyl, benzyl, p-methoxyphenyl and p-chlorophenyl) afford only the corresponding phosphiniminocyclotrisul-phurtrinitrides, R3PNS3N3 (I-V) in moderate to good yields. (p-ClC6H4)3P alone yields the disubstituted S4N4 derivative, 1,5-[(p-ClC6H4)3PN]2S4N4 (VI) in low yield which undergoes a ring contraction in solution. Among the red crystalline compounds I-V, those containing aliphatic substituents on phosphorus (I-III) are less stable both in solid and solution phases than those containing aromatic substituents (IV and V). Various spectroscopic data have been discussed. © 1989.

Inorganica Chimica Acta

Cyclic SN compounds and phosphorus reagents part 6. Reactions of S4N4 with ...

(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.

Journal of the Chemical Society, Dalton Transactions

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	ZAAC ‐ Journal of Inorganic and General Chemistry
ISSN	00442313
Open Access	No