Fluorénacènes et fluorénaphènes Synthèses dans la série des indéno-fluorènes,XIX Dérivés tétraméthylés du trans-fluorénaphène et du trans-fluorénacène

By condensation of isophthaloyldichloride resp. of terephthaloyldichloride with 4-bromo-1,2-xylene according Friedel-Crafts, followed in each case by a double cyclisation and a final reduction, the 2,3,9,10-tetramethyl-7,12-dihydro-indeno[1,2-a]fluorene resp. the 2,3,8,9-tetramethyl-6, 12-dihydro-indeno[1,2-b]fluorene are synthesized.     

Fluorénacènes et fluorénaphènes synthèses dans la série des indéno-fluorènes,XVII. Dérivés méthylés du cis-fluorénacène,du trans-fluorénacène et du trans-fluorénaphène

By condensation of the chlorides of the three 9-oxo-fluorene-2-, -3-, and -4-carboxylic acids with 4-bromo-1,2-xylene on one side, and of the chlorides of o-bromobenzoic acid, 2-bromo-4-methyl-benzoic acid and 2-bromo-4,5-dimethyl-benzoic acid with fluorene, 2-methylfluorene and 3-methylfluorene on the other side, followed by direct or indirect cyclisation and by final reduction, several new methyl derivatives of the indenofluorenes I, II and IV are synthesized.     

Fluorénacènes et fluorénaphènes Synthèses dans la série des indéno-fluorènes,XV [1] Méthyl-5-dihydro-10, 12-indéno [2, 1-b]fluorène

Starting from α-methylchalcone and diethyl ketone the title compound, II, has been synthesized in 6 steps (overall yield 26%). As an intermediate compound the gold yellow 10, 12-dioxoderivative of II was also obtained.     

Fluorénacènes et fluorénaphènes Synthèses dans la série des indéno-fluorènes,XVIII. Le diméthyl-5, 6-dihydro-7, 12-indéno[1, 2-a]fluorène

Starting from 3, 4-dimethylfluorene the title compound, 5, 6-dimethyl-7, 12-dihydro-indeno[1,2-a]fluorene (IV), is synthesized in four steps (overall yield 9%). The same hydrocarbon is also obtained in four steps starting from the phthalaconecarboxylic acid of Gabriel. This corroborates the structure of IV.     

Fluorénacènes et fluorénaphènes Synthèses dans la série des indéno-fluorènes,XVI. Méthyl-5-, diméthyl-5, 6- et diphényl-5, 6-dihydro-11, 12-indéno [2.1-a] fluorène

Starting from 2-methyl- and from 2,3-dimethyl-1,4-diphenyl-butadiene-1, 3 respectively, the 5-methyl- and the 5,6-dimethyl-11, 12-dihydro-indeno[2.1-a]fluorene are synthesized in 4 steps. The 5, 6-diphenyl-11, 12-dihydro-indeno[2.1-a]fluorene is obtained by reduction of the already known 11, 12-dioxoderivative. Accesorily a new preparation of the unsubstituted hydrocarbon is described.     

Synthèse de flavones et de xanthones dans la série du benzo[4,5]thiophène

We describe the first synthesis of 2-arylbenzo[4,5]thieno-[2,3-b]pyran-4-one and of 2-arylbenzo [4,5] thieno [3,2-b] pyran-4-one, from benzo [4,5] thiophene and we have extended these cyclizations to obtain the heterocyclic analogs of the xanthones.     

Synthèses dans la série des bis-indéno-fluorènes,VIII. Méthyl-6-dihydro-9,15-7H-bis-indéno[2.1-b;2′.1′-g]fluorène

Starting from 5-benzoyl-2,4-dibromobenzoic acid and 3-methyl-fluorene, the 6-methyl-9,15-dihydro-7H-diindeno[2.1-b; 2′,1′-g]fluorene, a derivative of a mono-angular diindenofluorene has been synthesized in 5 steps (overall yield 1,5%).     

Synthèses dans la série des-indéno-fluorénes,VII. Le trioxo-5,12,13-dihydro-12,13-5H-bis-indéno[2.1-a; 2′.1′-g] fluoréne

Starting from 9-oxo-fluorene-1-carbaldehyde, the title compound, XII, a trioxoderivative of a new biangular diindenofluorene system, has been synthesized in 5 steps (overall yield 37,5%). The corresponding hydrocarbon could not be obtained by reduction of XII. Attempts to synthesize the isomer XX of the trioxoderivative XII are described.     

Prototropie et synthèses nouvelles dans la série des dihydro-5,6 hydroxy-4 pyrones-2 et pyridones-2

The multistep catalytic reduction of 6-methyl-4-hydroxy-2-pyrone allows isolation of two intermediate compounds: the biologically active parasorbic acid ( 5 ) and the 6-methyl-5,6-dihydro-4-hydroxy-2-pyrone ( 2 ). The desmotropic keto-enol equilibrium lies on the enol side, with the 4rhydroxy structure. Primary arylamines readily react with 2 , leading to corresponding 2-pyridones 8 ; with methylamine, the aliphatic intermediate 7 resulting from ring attack at the 2 position can be isolated. Also further functionnalization of both dihydropyrone and 2-pyridone is possible by selective bromination at position 3.     

Synthèses dans la série des bis-indéno-fluorénes III [1]. Dihydro-14, 15-13H-bis-indéno[2,1-a;1′,2′,-i]fluorène et dihydro-14, 15-8H-bis-indéno [2, 1-a;2′,1′-h]fluorène

Starting from 2-bromo-9-oxo-fluorene-1-carboxylic acid the biangular bis-indenofluorene 14, 15-dihydro-13H-diindeno[2, 1-a; 1′, 2′-1]fluorene (VIII) and the monoangular 14, 15-dihydro-8H-diindeno[2, 1-a; 2′, 1′-h]fluorene (XI) have been synthesised in 6 resp. 7 steps (overall yield 22% resp. 18%). As intermediate compounds the 14-oxoderivatives of VIII and XI were also obtained.     

Synthèses dans ka série des bis-indéno-fluorènes II. Le dihydro-10,15-5H-bis-indéno [1, 2-a;2′,1′-i] fluorène

The biangular bis-indeno-fluorene 10,15-dihydro-5H-diindeno [l, 2-a; 2′, 1′-i]-fluorene (XII) has been synthesised in 6 steps starting from 1-(o-carboxyphenyl)-fluorenone (overall yield 21%). As an intermediate the 5,10,15-trioxoderivative of XII and, accessorily, its 5,10-dioxoderivative were also obtained.     

Recherches dans la série des cyclitols,XLI. Synthèses de deux cyclopentane-pentols

Two new cyclopentane-pentols, namely the 1, 2, 3, 4/5- and 1, 2, 3/4, 5-isomers have been prepared by hydroxylation of the three 3, 4, 5-trihydroxy-1-cyclopentenes. The stereoselectivity of some hydroxylating agents is discussed.     

Recherches dans la série des cyclitols XLIV. Synthèses de cycloses dérivés du cyclopentane

The conversion to free ketoses by transketalisation of ethylene-ketal and/or isopropylidene derivatives of polyhydroxy-cyclopentanones has been investigated. The preparation of 2, 3-dihydroxy-cyclopentanone and of 2, 3-dihydroxy-cyclopentenone has been described.     

Synthèses dans la série des bis-indéno-fluorènes I. Le dihydro-13, 15-5H-bis-indéno[1, 2-a;1′, 2′-h]fluorène

The synthesis of 13,15-dihydro-5H-diindeno[1,2-a;1′,2′-h] fluorene in six steps starting from flourenone 4-carboxylic acid and 2,4-dichlorotoluene is described. As an intermediate product the 5, 13, 15-trioxo-derivative is obtained.     

Structure et synthèses nouvelles dans la série des amino-4 dihydro-5,6 méthyl-6 pyrones-2

Primary and secondary amines react with 4-hydroxy-5,6-dihydro-Z-pyrones at position 4, and not at position 2 as previously indicated. However, a new series of compounds is obtained by this reaction, some of them exhibiting therapeutic properties. Reactivities of dihydropyrones and pyrones are compared.     

Thio-I ehromannones 5,8-disubstituées et synthèses dans la série du thiéno[4,3,2-de] thiochromanne

With the aim of obtaining the thieno[4,3,2-de] thiochromane structure, various 5,8-disubstituted derivatives of [1]thiochromanone have been synthesized. The structures of the compounds thus obtained and of the intermediates used in their syntheses were confirmed by nmr spectroscopy or by chemical procedures.     

Diastéréotopies dans la série du benchrotrène

¹H and ¹³C spectra of mono-and disubstituted (benzene)-tricarbonylchromium complexes have been analysed. The influence of the substituents is discussed and special attention is paid to the diastereotopy resulting from different types of chirality. The racemic pseudosymmetric isomer and the two meso pseudoasymmetric isomers of the glycols (OC)₃CrC₆H₄(CHOHCH₃)₂ are compared. The stereochemical requirements are also examined.