Mecanisme de formation et de transformation des spirophosphoranes—IX: Reactions des spirophosphoranes a liaison PH avec les ethers vinyliques et les enamines

The reaction of 1,4,6,9-tetraoxa-5-phospha(V)spiro[4,4]nonane 1 with ethyl vinyl ether gives a spirophosphorane containing a PC bond, 5-(β-ethosyethyl)-1,4,6,9-tetra-oxa-5-phospha(V) spiro[4,4]nonane 2 (radical reaction), and a tricoordinated phosphorus compound, 2-(3,5-di-oxa-4-methylheptanoxyl)-1,3,2-dioxaphospholane 3 (ionic reaction). 2,2,3,3,7,7,9-Heptamethyl-1,4,6-trioxa-9-aza-5-phospha(V) spiro[4,4]nonane 6 gives exclusively a spirophosphorane containing a PC bond, 5(β-ethoxyethyl)-2,2,3,3,7,7,9-heptamethyl-1,4,6-trioxa-9-aza-5-phospha(V)spiro[4,4]nonane 7. The reaction of 1 with alcohol or ethyleneglycol and enamine yields a pentaoxyspirophosphorane and an amine by an oxidation-reduction condensation. Suggested mechanisms of these reactions are presented.     

Synthèse et propriétés photochromiques de 1, 3-dihydrospiro[2H-indole-2,3′-[3H]pyrimido[5,4-f][1,4]benzoxazines] et de 1,3-dihydrospiro[2H-indole-2,7′-[7H]thiazolo[5,4-f][1,4]benzoxazines]

Synthesis and Photochrmic Characteristics of 1,3-Dihydrospiro[2H-indole-2,3′-[3H-]pyrimido[5,4-f][1,4]benzoxazines] and 1,3-Dihydrospiro[2H-indole-2,7′[7H]thiazolo[5,4-f][1,4]benzoxazines] Two new series of 1,3-dihydrospiro[2H-indole-ozazine] derivatives were synthesized, the 1,3-dihydrospiro[2H-indole-2,3′-[3H]pyrimido[5,4]pyrimido[5,4-f][1,4]benzoxaines] 4-10 and the 1,3-dihydrospiro[2H-indole2,7′-[7H]thiazolo-[5,4-f][1,4]benzoxaines] 11–17 . These series extend the available range of photochromic properties (rate constant of thermal bleaching, UV/VIS spectrum of the opened coloured form, and photocoloration yield), an interesting feature of variable-transmission materials. The synthesis of these compounds (Scheme 1) required the preliminary synthesis of intermediate β-hydroxy-α-nitrosotherocycles 18 and 19 (Scheme 2). Important amounts of a coloured, non-photochromic, stable secondary product (See 20 ) were found in the condensation in the spiro[indole-thiazolobenzoxazine] series. The photochromic characteristics of the new derivatives were determined using a flash-photolysis apparatus coupled to a fast-scanning spectrometer. The role of the heteroatoms in the oxazine moiety and the role of substitutents in the indole moiety were investigated quantitatively through the study of the photochromic properties and the solvent effects. The presence of an S-atom gives rise to interesting properties which open up new prospects for synthesis and application.     

Synthèse d'éthers diéthylamino éthyliques de bibenzofurannes et de bis-benzofuryl cétones,comme analogues pharmacochimiques de la Tilorone

The diethylaminoethyl ethers of various bis[Bz-hydroxy]bibenzofurans have been synthesized, either from 2-hydroxy-5-methoxybenzyl alcohol, or from benzofurancarboxylic acids. The corresponding ethers of bis[Bz- hydroxy-2-benzofuryl]methanones were prepared from methoxysalicyl-aldehydes.     

1H and 13C NMR signal assignments of some new spiro[7H-benzo[de]anthracene-naphthopyrans

The complete 1H and 13C NMR signal assignment of four new photochromic spiro[7H-benzo[de]anthracene-naphthopyrans] was achieved using one- and two-dimensional methods (DEPT, COSY, HSQC, HMBC, NOESY).     

Synthèse par cyclisation nucléophile de dérivés de sucres portant un hétérocycle inséré en spiro. Note de Laboratoire

Synthesis of Sugar Derivatives Bearing a Spiro Heterocycle via Nucleophilic Cyclization Treated with the 1,4-binucleophiles 1,2-diaminoethane, 2-aminoethanol, 2-aminoethanethiol, L -cysteine, o-phenylenediamine, o-aminophenol or o-aminothiophenol the ketosugar derivative 1 gave in good yields the corresponding spiro derivatives 2–8 . In each case, the reaction was stereospecific leading to the isomer bearing the N-atom on the endo face of the bicyclic starting material. Starting from the sugar enone 9 , the aromatic 1,4-binucleophiles led stereospecifically to the spirobenzo [b]-diazepine 10 , -oxazepine 11 or -thiazepine 12 . In one case, an imine (13) was isolated. As 13 cyclized to 6 , the intermediate formation of these kind of derivatives could be considered as a common step for all these reactions.     

Di­methyl 2‐(4‐bromo­phenyl)‐10,11‐di­methoxy‐2,3,7,8‐tetra­hydro­spiro­[azepino[2,1‐a]­iso­quinoline‐3,9′‐fluorene]‐4,5‐di­carboxyl­ate

The title compound, C₃₈H₃₂BrNO₆, is a new photochromic tetra­hydro­azepinoiso­quinoline (THAI). The longest spiro bond [1.589 (4) Å] can be broken very easily by UV light, leading to ring opening. This explains the photochromic behaviour.     

Spiropyrans and spirooxazines. 1. Synthesis and photochromic properties of 9"-hydroxy- and 9"-alkoxy-substituted spironaphthooxazines

A procedure was developed for phase-transfer catalyzed alkylation of 5-hydroxyindolenine and 9"-hydroxy-substituted spiro[indoline-2,3"-naphtho[2,1-b]oxazines] by alkyl halides. New 9"-hydroxy- and 9"-alkoxy-substituted spironaphthooxazines, spirooxazinyloxyacetic acids, and their esters containing substituents with different length of the carbon chain in the indoline moiety were synthesized. The influence of the substituents on the spectroscopic properties of the starting and colored forms and the kinetic characteristics of photochromic transformations of 9"-substituted spironaphthooxazines in solutions and polymeric films was investigated. The bipolar merocyanine forms of spirooxazines were found to produce H-aggregates.     

Diénamines hétérocycliques. III. Réexamen de la réaction de la base de Fischer avec le tétracyanoéthylène

Heterocyclic dienamines III. A re-examination of the reaction of Fischer's base on tetracyanoethylene Depending on the order of addition, Fischer's base 5 (1,3,3-trimethyl-2-methylidene-indoline) reacts 1:1 with tetracyanoethylene to give either the tricyanovinylation product 6 or the spiro compound 7 . A skeletal rearrangement of a zwitterionic intermediate can explain the formation of the spiro compound. The latter undergoes a thermal isomerization yielding by ring expansion the tetrahydroquinoléine 8 . On reaction with LiAlH₄ or CH₃ONa 7 and 8 lead both to triazatetracycles. All structures are assigned on the basis of spectral data.     

An organic photochromic compound: (2S)‐2′‐ethoxy‐1,3,3‐trimethyl‐6′‐(piperidin‐1‐yl)spiro[indoline‐2,3′‐3′H‐naphtho[2,1‐b][1,4]oxazine]

In the course of our synthesis of hybrid photochromic compounds, the unexpected new organic photochromic title compound, C₂₉H₃₃N₃O₂, (I), was obtained. It is a derivative of the parent spirooxazine 1,3,3‐trimethyl‐6′‐(piperidin‐1‐yl)spiro[indoline‐2,3′‐3′H‐naphtho[2,1‐b][1,4]oxazine], (II). The 2′‐ethoxy group gives (I) different photochromic properties from its parent spirooxazine (II).     

Synthèse et étude de modèles de NADH à noyaux accolés en série pyrrolo[2,3-b] et [3,2-b]pyridines

Pyrrolo[2,3-b] and [3,2-b]pyridines derivatives, precursors for annealated NADH models have been prepared. Several methods for building a pyridinic annealates ring have been used starting from 2- or 3-aminopyrrole. The corresponding dihydropyridine structure leads to highly reactive NADH models compounds and are very much more stable than common models.     

Hydroxylation de l''estrone et de son acétate par le peroxyde d''hydrogéne en milieu superacide

Estrone 1a and its acetate 1b react with hydrogen peroxide in SbF₅-HF to give hydroxylated compounds. The formation of the dienone 2 can be accounted for by reaction of the electrophile H₃O₂⁺ on the neutral substrate, whereas formation of compound 3b implies electrophilic attack on the protonated ester 1b. Higher acidity favours rearrangement of the resulting ion 9 to yield, through a spiro intermediate, the ester 4b. Under the reaction conditions esters 3b and 4b]are slowly converted into the corresponding phenols 3a and 4a.     

Réductions chimique et électrochimique de benzopyranno-1 as-triazines

Electrochemical reduction of [1]benzopyranno[4,3-e]-as-triazinones gives 1,4-dihydro derivatives which can either rearrange into 4,4a-dihydro compounds or be reduced with ring contraction into benzopyranno-imidazolones. The reaction of Grignard reagents on benzopyrannotriazines leads to a reduction in –α position of the benzene ring (4,4a-dihydro). Electrochemical reduction gives the 1,4-dihydro derivative which rearrange into the 1,10a-dihydro compound. The 1,4-dihydro derivatives are reduced with triazine ring contraction to give benzopyrannoimidazoles. Dihydro-1,10a compounds can be reduced into imidazoles or into tetrahydro derivatives.     

Ring contraction during the 6pi-electrocyclisation of naphthopyran valence tautomers

The thermal and photochemical ring-opening of spiro(3H-naphtho[2,1-b]pyran-3,9'-thioxanthene-10,10-dioxide) results in the facile ring-contraction to 9-(naphtho[2,1-b]furan-2-yl)-9H-thioxanthene-10,10-dioxide . Similar behaviour is displayed by the isomeric spiro(2H-naphtho[1,2-b]pyran-2,9'-thioxanthene-10,10-dioxide) affording 9-(naphtho[1,2-b]furan-2-yl)-9H-thioxanthene-10,10-dioxide , though more severe reaction conditions were required. The comparative ease of this rearrangement for the isomers and was rationalised on the basis of the relative isomer populations of the ring-opened naphthopyrans. The rearrangement of simple mono- and bis-methylsulfonylphenyl substituted photochromic naphthopyrans , was examined; the former failed to rearrange whereas the latter could be induced to rearrange only under prolonged UV irradiation. The photochromism of diastereoisomerically pure sulfoxides derived from the oxidation of spiro(3H-naphtho[2,1-b]pyran-3,9'-thioxanthene) and spiro(2H-naphtho[1,2-b]pyran-2,9'-thioxanthene) resulted in conversion to the most thermodynamically stable trans-isomer in each case.     

Ring transformations of heterocyclic compounds. XXIII. The UV irradiation product of photochromic 2,4,6‐triaryl‐1‐(spiro[2H‐l‐benzopyran‐2,2′‐indoline]‐6‐yl)pyridinium salts ‐ A phenolate betaine or a pyridinium substituted merocyanine dye?

The synthesis of the novel 2,4,6‐triaryl‐1‐(spiro[2H‐1‐benzopyran‐2,2′‐indoline]‐6‐yl)pyridiniumper‐chlorates 4 by reaction of 5 ‐nitrosalicylaldehydes 6 with 1,3,3‐trimethyl‐2‐methyleneindoline ( 7 ) to 6‐nitro‐spiro[2H‐1‐benzopyran‐2,2′‐indolines] 1 , their stannous chloride reduction to the 6‐amino derivatives 8 , followed by a 2,6‐[C₅+N] ring transformation with 2,4,6‐triarylpyrylium perchlorates 9 , is reported. UV irradiation experiments in twenty solvents of different polarity prove their photochromic properties and show that the photochemically generated negative solvatochromic dyes 5 , formed by ring opening of the benzopyran moiety of 4 , are rather merocyanine than pyridinium phenolate betaine dyes.     

New maleimide spirobenzopyran derivatives as photochromic labels for macromolecules with sulfhydryl groups

Two new photochromic labels of spiro[chromene-2,2’-indole] series supplied with 5-positioned maleimide moieties suitable for labelling macromolecules with sulfhydryl groups were synthesized.     

Etude par RMN 1H d'hétérocycles voisins de l'oxazaphospholane-1,3,2: III—Le phényl-1 dioxa-2,8 aza-5 phosphav-1 bicyclo[3.3.0]octane et le dioxa-1,6 diaza-4,9 phosphav-5 spir[4.4]nonane

The interpretation in terms of conformational analysis of ¹H n.m.r. parameters of 1-phenyl-2,8-dioxa-5-aza-1-phospha^v bicyclo[3.3.0]octane is consistent with a rigid envelope conformation for each 5-membered ring and a planar nitrogen atom. In the case of 1,6-dioxa-4,9-diaza-5-phospha^vspiro[4.4]nonane, the same procedure shows librational motions around the C? C bond.     

Synthèse et réactivité de dihydrotriazines et de dihydrotriazolotriazines

Generally, 4,5-dihydro-3triazinones have been prepared by a basic hydrolysis of 3-methylmercapto-4,5-dihydrotriazines. Of the serveral methylation methods, namely, diazomethane, methyliodide, dimethyl sulfate all in the presence of sodium methylate or silver carbonate, only methyl bromide in the presence of phase transfer catalyst was sucessful in producing all of the N-2 and/or N-4 methylate compounds. Two unequivocal syntheses of dihydrotriazolo[4,3-b]triazine are reported.     

The reaction of spiro[indoline‐naphthopyrans] with nitrogen oxides. Not a case of biradical double trapping

The reactions of six differently substituted photochromic spiro[indoline‐naphtopyrans] with ·NO or ·NO₂ under normal daylight conditions have been investigated by means of EPR spectroscopy along with those of three structurally related spiro[indoline‐benzopyrans]. The spectra due to cyclic oxynitroxides originating from double trapping of biradicals by ·NO were observed with the three latter derivatives, this finding being in agreement with previous results. Similar signals were also observed with the six former compounds, but in this case they were responsible for just a minor component of the spectra, the main spectral signals being due to hitherto unreported paramagnetic species that on the basis of their spectral parameters are identified as iminoxy radicals. DFT calculations at the B3LYP/6‐31G* level carried out on a variety of radicals support this assignment. Copyright © 2009 John Wiley & Sons, Ltd.     

Etude de la réaction de l'acé'tylacé'tate d'éthyle avec les diamino-1,5 imidazoles

The condensation of 1,5-diaminoimidazoles with ethyl aceto-acetate gives two types of compounds: imidazo[1,5-b]-1,2,4-triazepinones and imidazo[4,5-b]pyridinones. The structure of these compounds is demonstrated by rmn and mass spectroscopy. The formation of imidazo[4,5-b]pyridinones from imidazo[1,5-b]-triazepinones through a new transposition is also shown.     

Transferts d'hydrogènes dans les cations radicaux ethylène-acetals dérivés de cyclopentanones et cyclohexanones

Hydrogen Transfer during Decompositions of Molecular Ions of Acetals Derived from Substituted Cyclopentanones and Cyclohexanones The isomerisation process of ethylene-acetal radical ions of low internal energy has been reinvestigated in more detail. The ring contraction of cyclohexane derivatives into methylcyclopentanes is quite general for these ions. The relative rates of [1, n] H transfers to the C free radical resulting from C? C cleavage α to the acetal group plays the most important part in the mechanism.