PHOSPHORUS-NITROGEN COMPOUNDS. PART 52.1 THE SYNTHESIS OF SOME 1,3,2-BENZODIAZAPHOSPHORINE 2-OXIDES AND 2-SULPHIDES

Abstract

The reactions of 4-methyl-2-[N-(p-toluidinyl)methyl]aniline with phosphorus oxychloride, thiophosphoryl chloride, and their derivatives yield 1,3,2-benzodiazaphosphorine 2-oxides and 2-sulphides. Their ¹H NMR and infrared spectra are discussed. Related 1,3,2-benzodiazophosphorine and 1,3,2-dibenzodiazaphosphocine 2-oxides and 2-sulphides are compared.     

STUDIES ON ORGANOPHOSPHORUS COMPOUNDS XXX. MASS SPECTROSCOPIC INVESTIGATION OF 2-ALKYL-2-OXO-1,3,2-DIOXA-PHOSPHORINANE AND-PHOSPHEPANE

Abstract

The mass spectra of 2-alkyl-2-oxo-1,3,2-dioxa-phosphorinane and-phosphepane showed that the ring opening was in competition with the cleavage of the P[sbnd]C bond. According to the fragmentation pathway, which was dependent on the structure of exocyclic substituents on phosphorus, the 2-alkyl-2-oxo-1,3,2-di-oxa-phosphorinanes can be classified in two categories. The main process in category A was the ring opening and/or C[sbnd]C bond cleavage. While in category B the cleavage of P[sbnd]C bond was predominant. However, for 2-alkyl-2-oxo-1,3,2-dioxa-phosphepane. no matter how the structure of 2-alkyl group was, the ring opening was a dominant process.     

THE MASS SPECTRAL FRAGMENTATION OF SULFENAMIDES AND RELATED COMPOUNDS

Abstract

Plausible mechanistic interpretations of the major ions formed in the mass spectrometric fragmentation of a number of sulfenamides and related derivatives are presented. High resolution mass spectrometry was used to determine the composition of most of the ions investigated.     

ZERO VALENT METAL COMPLEXES OF 5,5-DIMETHYL-2-R-1,3,2-DIOXAPHOSPHORINANES

Abstract

The preparation and characterization of some Ni(0) and Pt(0) complexes of 5,5-dimethyl-2-phenoxy-1,3,2-dioxaphosphorinane is reported. This phosphite, which contains a single six-membered ring, displays donor-acceptor properties intermediate to P(OCH₂)₃CR and trialkyl or triaryl phosphites. The conformation of the ligand in the complexed form is proposed to be a chair ring with an axial phenoxy group.     

STUDIES ON ORGANOPHOSPHORUS COMPOUNDS PART IX.1 THE ACTION OF Di-, TRIALKYL PHOSPHITES AND THIOL ACIDS ON SOME ENAMINOLACTONES

Abstract

Di-, and trimethylphosphites react with enaminolactone, 4, only in methanol to give N-benzoyl-3-phenyl-3-phosphonoalanine-trimethylester (7) in good yields. Diphenylphosphinodithioic acid also reacts with 4 to give N-benzoyl-3-phenylcysteine-methyl ester-diphenylphosphinodithioate (9). A mechanism is proposed to account for the formation of 7. Compatible analytical and spectroscopic results were obtained for the new compounds.     

SOME HETEROCYCLIC PHOSPHOROCHLORIDATES AND THE FORMATION OF OTHER HETEROCYCLIC ORGANOPHOSPHORUS COMPOUNDS

Abstract

Pyrrolidine, morpholine, and β-hydroxyethylmorpholine have been phosphorylated with phosphorus oxychloride, phenylphosphorodichloridate, p-chlorophenylphosphorodichloridate and thiophosphoryl chloride. The resultant phosphorodichloridates have been condensed with a wied range of nucleophilic reagents, e.g. amines, hydrazines, phenols and isobutanol. Piperazine with phosphorus oxychloride (2 mols) gave the N(1) N(4)-diphosphorotetrachloridate, which was characterized as the tetracyclohexylamidate. β-Hydroxyethylpiperazine was similarly phosphorylated to the N,O-diphosphorotetrachloridate which was characterized as the tetraphenylhydrazidate.

Condensation of pyrrolidine (2 mols) with phosphorus oxychloride (1 mol) afforded N,N′-dipyrrolidinophosphorochloridate which was reacted with phenylhydrazide and sodium azide. The phosphoroazide with triphenylphosphine afforded the corresponding triphenylphosphinimine. N-Phenyl N′-pyrrolidinophosphorochloridate with aqueous pyridine gave the corresponding pyrophosphoramide and the stability of the pyrophosphoramide towards hydrolysis was examined. 1,2-Cyclohexanediol was phosphorylated with phenylphosphorodichloridate and thiophosphorylchloride. Trans-4-t-Butylcyclohexyl N,N′-diphenylhydrazinophosphorothioate by reaction with formaldehyde gave a tetra-azaphosphorine P-sulfide. Trans-4-t-Butylcyclohexyl N-phenyl N′-phenylphosphorodiamidic hydrazide reacted with 1,4-dibromobut-2-ene to give a 1,2-diazahex-4-ene.     

THE MASS SPECTRA OF PHOSPHONYL COMPOUNDS PART 31. DIMETHYL AND DIETHYL ALKANE- AND SUBSTITUTED-METHANE PHOSPHONATES

Abstract

The electron impact mass spectra of 28 related phosphonates have been determined. Ethyl, iso-propyl and tert-butyl groups which are bound directly to phosphorus, fragment to the corresponding alkenes; similar iso-propyl and tert-butyl groups in the dimethyl esters also fragment to ethylene and propene respectively, i.e. the P-alkyl group rearranges with transfer of the elements of a methyl group to the phosphorus ion. The diethyl alkenephosphonates undergo double hydrogen rearrangements of an ethoxy group to give dihydroxyphosphonium ions. The di- and trihydroxyphosphonium ions have a characteristic fragmentation which involves loss of water. This characteristic has been used as evidence for the rearrangement of a phosphacylium ion to a dihydroxyphosphonium ion. Some other unusual rearrangements involving the combination of the groups bound to phosphorus and oxygen have been observed.     

STUDIES OF HETEROCYCLIC COMPOUNDS: VI1 THE MASS SPECTRA OF SOME 2-THIOPHENEMERCURIC DERIVATIVES

Abstract

The mass spectra of some 2-thiophenemercuric derivatives are determined and the fragmentation interpretations are based on mechanistic analogy and supported in some cases by metastable peaks and low energy mass spectra. They all fragment ultimately to the 2-thienyl cation formed either through a two-step process, by cleavage of Hg[sbnd]X bond to give the 2-thienylmercuric cation, followed by extrusion of mercury, or by a one-step process through cleavage of carbon-mercury bond. Their base peaks being the C₃H₃ ⁺ion (m/e 39).     

THE STUDY OF 2-CHLORO-5,5-DIMETHYL-2-OXO-1,3,2-DIOXAPHOSPHORINANE IN SOLUTIONS BY MOLECULAR DYNAMICS METHODS USING IR AND RAMAN SPECTROSCOPY

Abstract

2-Chloro-5,5-dimethyl-2-oxo-1,3,2-dioxaphosphorinane has been studied in CCl₄, CHCl₃ and CD₃CN solutions by IR and Raman line shape analysis. Equilibrium process of dimerization and ring conversion in CCl₄ solutions have been considered. On the contrary to the commonly expected dominance of the conformer with the equatorial oriented P[dbnd]O bond for 2-halo-2-oxo-1,3,2-dioxaphosphorinanes, it was found that for the 2-chloro derivative both conformers are nearly equally distributed. It has been shown that the interactions induced absorption is an important mechanism of relaxation in the studied compound and this mechanism gives significant contribution to the total IR band broadening, while the interaction induced light scattering is negligible. The obtained results show that the molecular dynamics method can be useful in studying cyclic compounds in solutions.     

有机磷化合物的质谱研究：ⅢO—乙基—N_异丙基（取代硫脲基）硫代磷酰胺酯

本文对新合成的19个O-乙基-N-异丙基(取代硫脲基)硫代磷酰胺醋进行了质谱研究。讨论了P—N键的断裂,包括简单断裂和重排反应、失HS·反应及硫脲N上不同取代基的影响等问题。在亚稳态测定和高分辨精确质量测量的基础上得到了这类化合物的断裂规律和质谱特征。     

PHOTOCHEMISTRY OF 2-MERCAPTOPYRIDINES. PART 3. EPR STUDY OF PHOTOPRODUCTION OF HYDROXYL RADICALS BY N-HYDROXYPYRIDINE-2-THIONE USING 5,5-DIMETHYL-1-PYRROLINE N-OXIDE IN AQUEOUS SOLUTIONS*

Abstract— N-Hydroxypyridine-2-thione, 2-S-PyrNOH, a potent antimicrobial, antifungal and anticancer agent, is photochemically active and upon UV irradiation generates free radicals. We have employed EPR and the spin-trap 5,5-dimethyl-l-pyrroline TV-oxide (DMPO) to investigate the photochemistry in aqueous solutions of 2-S-PyrNOH (used here in the form of a sodium salt, 2-S-PyrNONa). We found that upon photoactivation 2-S-PyrNONa can follow two different pathways: it can produce hydroxyl radicals and/or it can act as a photoreducing agent. The capacity of 2-S-PyrNONa to produce “OH” radicals has been demonstrated by: (1) EPR detection of the DMPO/OH adduct in UV-irradiated samples; (2) inhibition of the DMPO/OH formation by OH scavengers such as methyl alcohol, formate and DMSO and (3) by detection of EPR signals of DMPO adducts with radicals derived from reaction of OH with these inhibitors. The photoreductive capacity of 2-S-PyrNONa was deduced from the observation that the amplitude of the EPR signal of the spin adduct DMPO/OH decreased on UV irradiation in air-free pH 7.0 buffers and that the signal recovered in the dark and after aeration. The ability to generate free radicals upon UV irradiation suggests that 2-S-PyrNONa can be regarded as a potential photocytotoxic agent. This feature may be relevant to the biological action of this compound. Our findings also emphasize that caution should be used when 2-S-PyrNOH is employed as a source of OH radicals in biological or chemical systems.     

N-取代苯并咪唑和N-取代-2-硫代噻唑烷酮类化合物的质谱研究

本文所研究的7种N-取代苯并咪唑和硫代噻唑烷酮类化合物是一类新合成的具有较高杀菌活性的化合物。本文利用电子轰击质谱技术对表中所列的化合物进行了研究。在高分辨精确质量测量和亚稳离子测定的基础上着重讨论了分子内3、4位C—C键的断裂和与杂环     

PHOTOCHEMISTRY OF 2-MERCAPTOPYRIDINES. PART 1. AN EPR AND SPIN-TRAPPING INVESTIGATION USING 5,5-DIMETHYLl-PYRROLINE N-OXIDE IN AQUEOUS AND TOLUENE SOLUTIONS*

Abstract We have employed EPR and the spin trap 5,5-dimethyi-1-pyrroline N-oxide (DMPO) to investigate the photochemistry of pyridine-2-thione (2-S-PyrH), N-hydroxypyridine-2-thione (2-S-PyrNOH), and its sodium salt, (2-S-PyrNONa), and disulfides, 2,2′-dithiobis (pyridine N-oxide) [(2-S-PyrN→O)₂] and 2,2′-dithiodipyridine [(2-S-Pyr),]. We have found that upon UV irradiation they generate aromatic thil radicals, 2–'SPyr and 2–'S-PyrN → O, detected as DMPO adducts, DMPO/2–'S-Pyr ( 1 ) and DMPO/2–'S-PyrN→O (2). In aqueous solution (pH 7) hyperfine splitting constants (hfsc) were determined to be for 1: a_N= 14.92 G, a_H^β= 16.57 G, and for 2: a_N= 14.78 G, a_H^β= 16.05 G. In toluene hfsc were 13.09 G, 13.93 G for 1, and 13.25 G, 12.04 G for 2. Irradiation of 2-S-PyrH and DMPO in aerated pH 7 buffer generated the DMPO/-O₂,- radical (3a, a_N= 14.10 G, a_H^β= 11.40 G, a_H^γ= 1.18 G), while in aerated toluene DMPO/.O₂H was formed (adduct 3b, a_N= 12.74 G, a_H^β= 10.41 G, a_H^γ= 1.295 G). In both systems adduct 1 was also observed. Because compounds possessing the pyridine-2-thione moiety show antifungal, antibacterial and anticancer properties, it is likely that the ability to photogenerate free radicals may be pertinent to their biological activity.     

SPECTROSCOPIC STUDIES OF CUTANEOUS PHOTOSENSITIZING AGENTS—II. SPIN TRAPPING OF PHOTOLYSIS PRODUCTS FROM SULFANILAMIDE AND 4-AMINOBENZOIC ACID USING 5,5-DIMETHYL-1-PYRROLINE-1-OXIDE

Abstract— The photodecomposition of sulfanilamide, 4-aminobenzoic acid and related analogs in aqueous solution has been studied with the aid of spin traps 5,5-dimethyl-1-pyrroline-1-oxide (DMPO) and CH₃NO₂ as well as by direct electron spin resonance techniques. The NH₂ radical was trapped by DMPO during the photolysis of aqueous solutions of sulfanilamide with a Xe arc lamp. Studies with [¹⁵N¹]-sulfanilamide indicated that the NH₂ radical was generated by homolytic fission of the sulfur-nitrogen bond. Under the same conditions DMPO trapped the H and SO⁻₃ radicals during photolysis of sulfanic acid. Direct photolysis of sulfanilamide, sulfanilic acid and Na₂SO₃ in the absence of any spin trap yielded the SO⁻³ radical. Photolysis of 4-aminobenzoic acid at pH 7 gave the H radical which was trapped by DMPO. At low pH values OH and C₆H₄COOH radicals were generated during the photolysis of 4-aminobenzoic acid. No e⁻_aq were trapped by CH₃NO₂ when acid (pH 4) and neutral aqueous solutions of sulfanilamide or 4-aminobenzoic acid were photoirradiated. The mechanism of formation of known photoproducts from the free radicals generated by sulfanilamide and 4-aminobenzoic acid during irradiation are discussed. The free radicals generated by these agents may play an important role in their phototoxic and photoallergic effects.