Volume 32, Issue 8

2-Methyl-5-phenyl-2H-1,2,4,3λ 3 -triazaphosphole, which does not lend itself to oxidative additions alone, reacts smoothly with o-heterodienyl-phenols yielding tricyclic phosphoranes. The reaction involves an initial addition of the phenolic end to the P=N bond and a subsequent fast intramolecular addition of the heterodiene moiety to the phosphorus. The structure of the resulting phosphoranes is proposed to have all three fivemembered rings attached to the central trigonal bipyramidal phosphorus by one axial and one equatorial bond with the bond in common to the two condensed rings in axial position. NMR data back this proposal.

The title compounds 3 a-g are obtained from acetyl- and benzoylhydrazine with PCl 5 , with methyl- and phenylchlorophosphoranes, and with phosphonic and thiophosphinic chlorides. The monomeric oxadiazaphosphole proposed as an intermediate has been trapped in one case by methyl isocyanate in a 2 + 2 cycloaddition. Compounds 3 with Cl at P can undergo nucleophilic substitutions. HCl degrades 3 in a slow reaction after an initial addition to the intact tricyclic system.

The preparation, for the first time, of the complex iodo acids of mercury (II) with ether and pyridine of the formula H[HgI 3 ]2B (where B = ether or pyridine) is described. The chemical and physical properties of these acids and the UV and IR spectra of the pyridine compound are reported and discussed.

From weakly acidified solutions of sodium molybdate by addition of tetrabutylammonium ions an iso-octamolybdate [N(C 4 H 9 ) 4 ] 4 Mo 8 O 26 is formed whose anion has a structure different from the known alkali or ammonium octamolybdates. Single crystals are obtainable by reaction in organic solvents. The IR and Raman spectra are presented. The decomposition of the anion by aging in dichloroethane in solution was investigated by UV spectroscopy. This study offers new aspects concerning the mechanism of polymolybdate ion formation.

TiCl 4 and ZrCl 4 were found to form a series of adducts with trimethyl(methylene)phosphorane, none of which is soluble in common inert solvents. With dimethylaminotitanium chlorides, a dinuclear ylide 10 was obtained, containing a dititanacyclobutane ring system, in which the metal atoms are bridged by [xxx] groups. cp 2 TiCl 2 and cp 2 ZrCl 2 also form ylide adducts with (CH 3 ) 3 P=CH 2 in the ratio 1:2. The lithiated ylide converts both cp 2 TiCl 2 and cp 2 TiCl into the cyclic ylide complex (C 5 H 5 ) 2 Ti(CH 2 ) 2 P(CH 3 ) 2 (13). With lithiated (CH 3 ) 3 P=N–P(CH 3 )2=CH 2 , the related nitrido-bis-dimethylphosphoniummethylide derivative (15) could be isolated. 13 and 15 were characterized, inter alia by their ESR and mass spectra.

Relative intensities of specific fragments of azo and hydrazone tautomeres in mass spectra are discussed. Linear relationship is given between calculated Z H (Z A )-values and pK B - and Hammett σ·values respectively. Electron donating substituents will lead to the formation of hydrazone tautomeres.

The formerly unknown spiro systems Α-E with Ge, Si, N and O in the framework could be synthesized by reactions 1-6 and confirmed in their structure by elemental analysis, NMR, IR and Raman spectra (Tables I-IV).

The compounds with composition NPCl(NSOF) 2 (C 5 H 5 N)OH (1) and NPCl(NSOCl) 2 (C 5 H 5 N)OH (2) are prepared by reaction of cis-NPCl 2 (NSOX)2 (X = F, Cl) with pyridine in ether. The pyridinium derivatives are colourless crystalline solids. Tentative structure assignments are given based on NMR data.

Nuclear spin-spin coupling constants 1 J ( 31 P- 117 Sn) and 1 J ( 31 P- 119 Sn) are reported for trimethylstannyl phosphines of the type [(CH 3 ) 3 Sn] 3 _ n PR n (R = H, t C 4 H 9 , C 6 H 5 , Si(CH 3 ) 3 , Ge(CH 3 ) 3 ; n = 0, 1, 2, 3) and for some transition metal carbonyl complexes having these phosphines as ligands. It is possible to calculate the value of 1 J (P-Sn) by the empirical method of increments, if there is a large number of similar compounds.

Using collisional activation mass spectrometry the structures of the [M–HX] +• ions (X = OH, NH 2 ) from 5-phenylpentanol-1 (1), 5-phenylpentylamine (2) and 6-phenylhexanol-1 (3) have been established. Contrary to previous results it is shown for the first time that in addition to ionized 1-phenyl-alkenes-1 some other double bound isomers as well as phenylcyclopentane and phenylcyclohexane are formed. The results strongly suggest that the HX eliminations are induced by a selective activation of CH bonds.

Using time resolved ESR spectroscopy and photoflash conductivity the uncatalysed, first order decay of 2-hydroxy-propyl-2-peroxyl radicals and the uncatalysed, first order generation of O 2 ·̅ and H+ were measured to have the same rate constants. The formation of O 2 ·̅ and H + was measured in H 2 O and D 2 O and a kinetic isotope effect of k H /k = D 3.5 was obtained. Comparing the rate constants of the peroxyl radicals derived from methanol, ethanol and 2-propanol it was shown that the rate constant increases with increasing methyl-substitution. In 2-propanol water mixtures the rate constant of the 2-hydroxy-propyl-2-peroxyl radical increases only slightly with increasing polarity of the solvent. The experimental results are in accord with a mechanism which involves a cyclic transition state leading to a concerted elimination of HO 2 · followed by dissociation into H + and O 2 ·̅ .

Juglone and lawsone, both acid-base indicators, obtained from natural sources and give pink and red colours with aqueous alkalies, respectively. Their transition ranges are found to be pH 7.4–8.2 and 2.6–3.4. To establish the transition intervals, a buffer series ranging in the pH values from 2.0–2.2–2.4–2.6–2.8–3.0–3.2–3.4–3.6–3.8–4.0–4.2–4.4–4.6–4.8–5.0–5.2–5.4–5.6–5.8–6.0–6.2–6.4–6.6–6.8–7.0–7.2–7.4–7.6–7.8–8.0–8.2–8.4–8.6–8.8–9.0 has been used. Juglone can be used for the titrations of strong acids with strong bases and weak acids with strong bases and lawsone can be used for the titration of strong acids with weak bases only. Permanancy of the colours at the end point is one of their advantages.

Carbon subsulphide (C 3 S 2 ), prepared by pyrolytic reduction of CS 2 , reacts with 6-chloro-4-hydroxycoumarin and thiobenzamide to yield the polythiopyrones and thiazinethiones 5, 6 and 7. 2-Mercaptopyridine and C 3 S 2 give the mesoionic compound 8. Generally it can be shown that C 3 S 2 reacts to give higher condensed products.

2-Dicyanomethylene-1,3-indandione reacts with 2,6-disubstituted anilines to give aminophenyl-1,3-dioxo-2-indanyl-malononitriles. By heating or by photolysis HCN is eliminated from the adducts and deeply coloured aminophenyl-1,3-dioxo-2-indanylideneacetonitriles are formed. They are classified as merocyanine type polymethines. The irreversible change in colour occurs at temperatures above 70 °C, the adducts are therefore capable of indicating temperatures. Reaction of phenols with 2-dicyanomethylene-1,3-indandione yields hydroxyphenyl-1,3-dioxo-2-indanylideneacetonitriles, oxonole type polymethines with the properties of p H -indicators.

The specifically substituted derivatives 3b, 3c of the aminyl 3a and the corresponding carbon centered radicals 6b, 6c yield resolved analyzable ESR spectra. In these systems the unpaired electron is highly delocalized. The aminyl radicals 3a-3c form C—C dimers.

The synthesis of the 1,4-azarsenanium salts 3 and 6 is discribed. Conformation and configuration of the 1,4-oxa- and -azarsenanium salts have been studied via 1 H and 13 C NMR spectroscopy.

The preparation of the perisubstituted naphthalene derivatives 1-8 is described for the first time, and possible axial or axial and planar chirality of these compounds is investigated by means of dynamic 1 H NMR spectroscopy. Molecular chirality, caused by hindered rotation, can be proven for compounds 1 and 3 at room temperature and for 2 at 193 K by the observation of magnetic inequivalence of isochronous protons in a diastereotopic environment. Temperature-dependent 1 H NMR spectra indicate that for 2 the coalescence temperature lies between 193 K and 213 K, and above 320 K for 3. By assuming T coal- = 200 K for 2 and T coal . > 320 K for 3 the following ⊿G≠-values were estimated with the aid of known approximations from the 1 H NMR spectral parameters Δν = ν A -ν B and J AB for the methylene and methyl groups of the oxazoline system present in these species: ⊿G≠ (2) = 10.1 kcal/mole (at 200 K), ⊿G≠ (3) = 17.3 (16.2) kcal/mole (at 320 K). These ⊿G≠-values represent the energy barriers of a dynamic intramolecular process, presumably according to a more or less hindered rotation in the purely axially chiral molecules 2 and 3. With the aid of these ⊿G≠-values and model considerations a description of the energy profile diagram of the hindered rotation in compounds 2 and 8 is attempted.

The first synthesis of dimethylchlorflavonin (1; R = R′= CH 3 ), a derivative of naturally occurring rare fungal flavonoid chlorflavonin (1; R = R′= H) has been achieved.

Nocardamine was isolated from an unidentified Streptomyces, species X-14568, and its 1 H NMR and 13 C NMR spectra are assigned in detail. Reaction with iodomethane and silver oxide converts nocardamine to the tri-O-methyl ether which is a suitable derivative for electron-impact mass spectrometry. Fragmentation mechanisms of tri-O-methylnocardamine are discussed.

Treatment of 4-arylhydrazono-3-methyl-2-pyrazolin-5-ones (1 a-e) with dimethylsulphate afforded the N-methyl derivatives (2a-e) which on treatment with phenylmagnesium bromide gave the carbinol (8). The hydroxy pyrazolones (4a-e) were reacted with ethyl acetoacetate and diethyl malonate to give the a-N-methyl derivatives (5 and 6 a-e). The hitherto unknown 4-arylhydrazono-3-methyl-l-benzenesulphonyl-2-pyrazolin-5-ones (7 a, e-e) were now obtained and upon treatment with Grignard reagent gave 4-arylhydrazono-3-methyl-3,5,5-triphenylpyrazolines (7 a, c and d).

Treatment of 5-arylazo-2-thiohydantoins (2 a-c) with formaldehyde and the appropriate amine in ethyl alcohol led to the formation of the corresponding Mannich bases 3a-i. 2 a-c reacted with methyl bromoacetate and/or chloroacetic acid to give the esters 5 a-c and/or the free acids 5d-f, respectively. 5e also obtained by treating 5 b with aqueous sodium hydroxide (2%). 5 a-c were cyclised with acetic anhydride to give the bicyclic products 6 a-c. 5-Arylidene-2-thiohydantoins (7 a-e) reacted with acrylonitrile in pyridine to give 5-arylidene-3-β-cyano-ethyl-2-thiohydantoins (8a-e). 8 a-c were hydrolysed with a mixture of acetic-hydrochloric acid to give the corresponding acids 8f-h. Compounds 8a, b, d were alkylated with alkyl halides to give 10 a-e which when hydrolysed with acids gave compounds 13 a-c.

It was not possible to condensate the Si(NHCH 3 ) 2 unit of the title compound to a six-membered ring system. Instead a novel dispiro compound with an OSO unit inside the framework was obtained using (NH 4 ) 2 SO 4 as a catalyst (Scheme 1).

By the use of 13 C NMR spectroscopy the photolytical fragmentation of 1,2,3-thiadiazole-1,1,2-trioxides is demonstrated.

The position of substituents at C-5 or C-6 of pyrrolo[2,3-d]pyrimidines can be determined by 13 C NMR spectroscopy. The method can also be used for 7-deazanucleosides and allows the assignment of the position of side chains.