SYNTHESIS OF SPIRO [1,3-BENZODIOXOLE-2,4′-(3′H) QUINAZOLINES]

Abstract

In the present investigation, the authors could obtain a new series of spiranes (1) through the reaction of the high potential quinone tetrachloro-o-benzoquinone with 2-aryl-3-phenyl-3H-quinazoline-4-thiones. Thus, 2,3-diphenyl- (2a), 2-p-tolyl-3-phenyl- (2b) and 2-p-anisyl-3-phenyl- (2c)-3H-quinazoline-4-thiones react readily with tetrachloro-o-benzoquinone, in boiling toluene, to give the corresponding spiro-1,3-benzodioxole-2,4′-(3′H)-quinazolines (1a-c), respectively.     

Observation of several phase transitions in tetrachloro-o-benzoquinone using 35Cl nuclear quadrupole resonance

The temperature dependence of the ³⁵Cl nuclear quadrupole resonance spectra of tetrachloro-o-benzoquinone (TOB) is reported. An analysis of the change in line multiplicities suggests that TOB undergoes three phase changes in going from 77 to 330 K. The transition temperatures have been determined.     

The molecular structure of gaseous tetrachloro-p-benzoquinone and tetrachloro-o-benzoquinone by electron diffraction

The structures of tetrachloro-p-benzoquinone and tetrachloro-o-benzoquinone (p- and o-chloranil) have been investigated by gas electron diffraction. The ring distances are slightly larger and the carbonyl bonds slightly smaller than in the corresponding unsubstituted quinones. The molecules are planar to within experimental error, but small deviations from planarity such as those found for the para compound in the crystal are completely compatible with the data. Values for the geometrical parameters (r_a distances and bond angles) and for some of the more important amplitudes (l) with parenthesized uncertainties of 2σ including estimated systematic error and correlation effects are as follows. Tetrachloro-p-benzoquinone: D_2h symmetry (assumed); r(CO) = 1.216 Å(4), r(CC) = 1.353 Å(6), r(C-C) = 1.492 Å(3), r(C-Cl) = 1.701 Å(3), ∠C-C-C = 117.1° (7), ∠CC-C1 = 122.7° (2), l(CO)= 0.037 Å(5), l(CC) = l(C-C) - 0.008 Å(assumed) = 0.049 Å(7), and l(C-Cl) = 0.054 Å(3). Tetrachloro-o-benzoquinone: C_2v symmetry (assumed); r(CO) = 1.205 Å(5), r(CC) = 1.354 Å(9), r(C_cl-C_cl) = 1.478 Å(28), r(Co-C_cl) = 1.483 Å(24), r(C_o-C_o) = 1.526 Å(2), r(C-Cl)= 1.705 Å(3), <C_o-CO = 121.0° (22), ∠C-C-C = 117.2° (9), ∠C_co, ClC-Cl = 118.9° (22), ∠C_ccl, ClC-Cl = 122.2°(12), l(CO) = 0.039 Å(5), and l(C_cl-C_cl) = l(C_o-C_cl) = l( Co-Co) = l(CC) + 0.060 Å(equalities assumed) = 0.055 Å(9). Vibrational'shortenings (shrinkages) of a few of the long non-bond distances have also been measured.     

New method for detection and spectrophotometric determination of quinones

The reaction between 3-phenylthiazolidine-2,4-dione (I) and p-benzoquinone (II), tetrachloro-p-benzoquinone (III), and 1,4-naphthoquinone (IV) in ammoniacal medium is applied for detection and spectrophotometric determination of quinones. The absorbance-concentration relationship is linear up to 18 μg/ml of quinone concentration. The lower limits of identification in the detection reaction are 2.5, 3.0, and 1 μg for (II), (III), and (IV), respectively, which reflect high sensitivity. The reaction between (I) and quinones is proved to be a condensation reaction and highly selective.     

Stereoselective synthesis of Z-3-alkoxy-2-[(4′-methoxyphenyl)methylidene]-1(3H)-isobenzofuranones

Photoreorganisation of 2-alkoxy-2-(4′-methoxyphenyl)-1H-indene-1,3(2H)-diones in anhydrous acetone affords exclusively Z-3-alkoxy-3-[(4′-methoxyphenyl)methylidene]-1(3H)-isobenzofuranones. The products were identified by X-ray crystallography of one of them.     

Activated sterically strained C=N bond in <Emphasis Type="Italic">N</Emphasis>-substituted <Emphasis Type="Italic">p</Emphasis>-quinone mono- and diimines: XV. Synthesis,structure, and reactions with alcohols of <Emphasis Type="Italic">N</Emphasis>-carbamoyl-1,4-benzoquinone imines

The reaction of 4-aminophenols with N-nitrourea or with sodium cyanate in acetic acid gave the corresponding 4-ureidophenols which were oxidized to N-carbamoyl-1,4-benzoquinone imines, substituted N-(4-oxocyclohexa-2,5-dien-1-ylidene)ureas. N-(2,6-Dimethyl-4-oxocyclohexa-2,5-dien-1-ylidene)urea possessing activated sterically strained C=N bond reacted with alcohols to afford N-(1-alkoxy-2,6-dimethyl-4-oxocyclohexa-2,5-dienyl)ureas.     

Reactivity of olefin an acetylene complexes of platinum(0) towards tetrachloro-o-benzoquinone

Tetracloro-o-benzoquinone reacts with (diphenylacetylene)bis(tirphenylphosphine)platinum(0) to give the novel platinum(II) diphenylacetylene complex, Pt(C₆Cl₄O₂)PhCCPh)(PPh₃), (I), which reacts with hydrogen halides to give the compelexes cis-PtX₂(PhCCPh((PPh₃), (X = Cl or Br). Hydrogen chloride also readily removes the tetrachloro-o-benzoquinoneligand from the adducts Ni(C₆Cl₄O₂)(Ph₂PCH₂CH₂PPh₂) and M(C₆Cl₄O₂)(PPh₃)₂, (M = Pd or Pt) but it has no reaction upon Ir(Cl)(C₆Cl₄O₂)(CO)(PPh₃)₂ at room temperature. The acetylene in (1) is susceptible to nucleophilic attact and reaction with diethylamine gives the vinyl adduct Pt(C₆Cl₄O₂)(CPhCPh)NHEt₂)(PPh₃). Other reactions of (I) have also been studied. Attemps to prepare other olefin or acetylene complexes of platinum(II) by the action of tetrachlor-o-benzoquinone on the complexes Pt(L)(PPh₃)₂, (L = PhCCH,(Et)(Me)(HO)CCCC(OH)(Me)(Et), HOCH₂OH, CF₃CCCF₃, CF₂CF₂, CF₂CH₂ or trans-PhCHCHPh) are also described.     

Efficient one-pot synthesis of 1-alkoxy-2-arylaminoimidazolines from N-alkoxy-N-(2-aminoethyl)-2-nitrobenzenesulfonamides and arylisothiocyanates

A new synthetic approach towards 1-alkoxy-2-aminoimidazolines that uses N-alkoxy-N-(2-aminoethyl)-2-nitrobenzenesulfonamides as nucleophile reagents for the reaction with isothiocyanates is reported. Hence, the synthesis of 1-alkoxy-2-aminoimidazolines was performed in high yield with a one-pot procedure involving thiourea formation, nosyl group removal and spontaneous cyclization (42-77% overall yield).     

Oxidation-induced ring expansion of a 2-phosphino-2H-azirine

Oxidation of the 2-phosphino-2H-azirine 1 by preparative scale electrolysis quantitatively leads to the four-membered phosphonium heterocycle 3, while addition of tetrachloro-o-benzoquinone to 1 produces an eight-membered heterocycle 4 with 60 % yield. In both cases, the first step is the formation of a transient phosphorus centered radical cation 1^•+, which induces the cleavage of the CN bond and the ring expansion reaction of the azirine moiety affording the four-membered ring intermediate 2^•+.     

Transfer hydrogenation and transfer hydrogenolysis—21 : Dehydrogenation of alcohols by quinones

Dehydrogenation of benzyl-type alcohols and hydroaromatic compounds by 2,3-dichloro-5,6-dicyano-p-benzoquinone (DDQ) and tetrachloro-p-benzoquinone were examined, and the hydrogen transfer from 1-phenyl-1-propanol to DDQ was investigated in detail. The yield of the propiophenone increased when solvents which would be expected to increase the concentration of the charge transfer complex between the alcohol and DDQ were used. Initial rates of the reaction in dioxane were proportional to the concentration of the hydrogen donor and that of the hydrogen acceptor. In the dehydrogenation of several para- or meta-substituted 1-phenyl-1-propanols at 60°, ?3.30 was obtained as a value of reaction constant. Relative rates of the reaction of PhCH(OH)Et, PhCH(OD)Et, PhCD(OH)Et, and PhCD(OD)Et were 8.9,9.1,1.0 and 1, respectively. This result suggests that the transfer of the H atom attached to the α-carbon of the alcohol is the rate-determining step. This and some other results support a two-step ionic mechanism for the dehydrogenation of alcohols.     

Facile stereoselective synthesis of cis- and trans-3-alkoxyazetidin-2-ones

A highly stereoselective synthesis of cis- and trans-3-alkoxy-3-phenyl/benzylthioazetidin-2-ones is described. The reaction of α-chlorosulfide-β-lactams with various alcohols catalyzed by a Lewis acid such as ZnCl₂ in the presence of molecular sieves (3-4 Å) leads to cis-3-alkoxy-3-phenyl/benzylthio-β-lactams whereas treatment of potassium 2-alkoxy-2-phenylthioethanoate with appropriate Schiff's base using POCl₃ in the presence of triethylamine leads to the formation of trans-3-alkoxy-3-phenylthioazetidin-2-ones as major products.     

ORGANOPHOSPHORUS COMPOUNDS,XXVIII. THE REACTION OF TRIPHENYLPHOSPHINE SULFIDE WITH TETRACHLOROBENZOQUINONES

Abstract

The reaction of triphenylphosphine sulfide with tetrachloro-o-benzoquinone gives a complex of the corresponding hydroquinone and triphenylphosphine oxide. Elemental sulfur is the other product. The tetrachloro-p benzoquinone does not react to any noticeable extent under similar conditions. Several mechanisms are proposed to explain the results.     

Stereoselective synthesis of (E)-4-alkoxy-2-aryl-5-chloro-2-thiazolines

The first synthesis of the title compounds has been achieved starting from chloralamides by a route involving chemical and electrochemical steps. N-(1-Alkoxy-2,2,2-trichloroethyl)benzamides were efficiently prepared from chloralbenzamides and were electrochemically converted into N-(1-alkoxy-2,2-dichloroethyl)benzamides in high yields by cathodic reduction in a protic medium. Thionation of these compounds with Lawesson's reagent followed by basic treatment gave novel (E)-4-alkoxy-2-aryl-5-chloro-2-thiazolines in fair to quantitative yields.     

Stereoselective electrogeneration of (E)-4-alkoxy-2-phenyl-5-chloro-2-oxazolines by cathodic reduction of N-(1-alkoxy-2,2,2-trichloroethyl)benzamides

The first method for the synthesis of the title compounds has been established. Quantitative reactions of benzamides with chloral hydrate provided chloralbenzamides which were efficiently converted to N-(1,2,2,2-tetrachloroethyl)amides by treatment with phosphorus pentachloride. These compounds reacted selectively with alcohols under mild conditions to give N-(1-alkoxy-2,2,2-trichloroethyl)benzamides in high yields which were stereoselectively transformed to (E)-4-alkoxy-2-aryl-5-chloro-2-oxazolines in fair to good yields by electrochemical reduction under constant cathodic potential in an aprotic medium.     

Polymerization and oxidation of pyrrole by organic electron acceptors

Simultaneous chemical polymerization and oxidation of pyrrole have been initiated by organic electron acceptors, 2,3-dichloro-5,6-dicyano-p-benzoquinone (DDQ) and tetrachloro-o-benzoquinone(chloranil). The polypyrrole (PPY) complexes so produced are semiconductive and granular in nature. For the PPY–DDQ and PPY–chloranil complexes obtained from bulk polymerization, the respective electrical conductivities (σ) are of the order of 10^?1 and 10^?3 ohm^?1 cm^?1. However, σ is substantially lower for the complexes prepared in solvent media. Both complexes are relatively stable in the atmosphere. Thin uniform films of the PPY–organic acceptor complexes have also been synthesized on SnO₂ electrode by electrochemical polymerization in acetonitrile. The physicochemical properties of the PPY–organic acceptor complexes prepared chemically under the various experimental conditions are examined in detail.     

Reaction of N,N-diarylamidines with 3,4,5,6-tetrachloro-1,2-benzoquinone

A synthesis of 5,11b-dihydro-1H-dibenzo[d,f][1,3]diazepin-1-ones was found in the reaction of nitro-substituted N¹,N²-diarylamidines with 3,4,5,6-tetrachloro-1,2-benzoquinone. In contrast, 6,7,8,9-tetrachlorodibenzodioxins were obtained from reaction of N¹,N²-diphenylpropionamidine and N¹,N²-di-(4-tert-butylphenyl)acetamidine with 3,4,5,6-tetrachloro-1,2-benzoquinone.     

Study of the reaction of 3,6-di-<Emphasis Type="Italic">tert</Emphasis>-butyl-<Emphasis Type="Italic">о</Emphasis>-benzoquinone with organozinc and organocadmium compounds

The effect of substituents in the reactions of 3,6-di-tert-butyl-о-benzoquinone with organozinc and organocadmium compounds, leading to three types of products: 3-alkyl-6-tert-butyl-о-benzoquinones, 4-alkyl-3,6-di-tert-butyl-о-benzoquinones, and 2-alkoxy-(or 2-phenoxy)-3,6-di-tert-butylphenols. Correlation analysis gave evidence to show that the first- and second-type products are formed by nucleophilic 1,2- and 1,4-addition, while substituted phenols result from single-electron transfer.     

Study on a single flow acid Cd–chloranil battery

This paper describes a novel redox flow battery–single flow acid Cd–chloranil battery. The electrolyte of this battery for both negative electrode and positive electrode is the aqueous intermixture of H₂SO₄–(NH₄)₂SO₄–CdSO₄, the negative electrode is inert metal such as copper foil, and the positive electrode is an insoluble organic material, tetrachloro-p-benzoquinone (chloranil). Typically, the electrolyte is continuously circulated to pass though the cells by means of a single pump as the battery is on duty. There is no requirement for a membrane. Tetrachloro-p-benzo-hydroquinone is oxidized to chloranil at positive electrode and the cadmium ions is reduced to cadmium and electroplated onto the negative electrode during charge. The reverse occurs during discharge. Results obtained with a small laboratory cell show that high efficiencies can be achieved with an average coulombic efficiency of 99% and energy efficiency of 82% over 100 cycles at the current density of 10 mA cm^?2.     

Development of non-enzymatic strip for simple and selective determination of urea in water and biological samples

A simple and selective method for the determination of urea based on the paptode technique is described. The sensor was constructed by immobilizing an ionophore on a TLC strip. The procedure is based on the nucleophilic displacement of urea with tetrachloro-p-benzoquinone (chloranil) as an ionophore, and the formed violet-color product was detected using a flatbed scanner. The color of each spot was analyzed to red (R), green (G) and blue (B) values from 0 to 255 using a program written in visual basic (VB) programming language. The calibration graph obtained with the proposed sensor was linear over the range of 0.05?C10.00?mg?L^?1 with a detection limit of 0.01?mg?L^?1 for urea. Parameters such as pH and concentration of chloranil were optimized. The proposed sensor was successfully applied for the determination of urea in bovine serum, urine and tap water samples.     

Electrochemically induced chain transformation of salicylaldehydes and alkyl cyanoacetates into substituted 4H-chromenes

Electrolysis of salicylaldehydes and alkyl cyanoacetates in ethanol in an undivided cell in the presence of sodium bromide results in the formation of substituted alkyl 2-amino-4-(1-cyano-2-alkoxy-2-oxoethyl)-4H-chromene-3-carboxylates in 85-95% yields.