Naphthomoles. 7. Synthesis of 4,11-dimethoxynaphtho[2,3-f]indole-5,10-dione and 4-methoxynaphtho[2,3-f]-indole-5,10-dione

4,11-Dimethoxynaphtho[2,3-f]indole-5,10-dione and 4-methoxynaphtho[2,3-f[indole-5,10-dione have been synthesized by the Leimgruber-Batcho reaction from 1,4-dimethoxy-2-methyl-3-nitroanthraquinone.Russian University of Chemical Technology, Moscow 125190. Center for Drug Chemistry, All-Russian Scientific Research Institute for Pharmaceutical Chemistry, Moscow 119815. Translated from Khimiya Geterotsklicheskikh Soedinenii, No. 8, pp. 1050–1054, August, 1996. Original article submitted March 20, 1996.     

Molecular structure of 2-phenyl-2-selenoxo-2-phosphabicyclo[4.4.0]decan-5-one

This paper reports on an X-ray diffraction study of one of the stereoisomers of 2-phenyl-2-selenoxo-2-phosphabicyclo[4.4.0]decan-5-one. The effect of the nature of the atom (O, S, Se) on bond lengths, bond angles, and conformation parameters in the series of stereoisomer heteroanalogs is considered. Deceased. Translated fromZhurnal Strukturnoi Khimii, Vol. 38, No. 3, pp. 547–553, May–June, 1997.     

Synthesis of 2-Phenyl-3-oxa-5-azatricyclo[4.4.0.02 , 7]decan-4-one

Cleavage of the lactone ring in 7-phenylbicyclo[3.1.1]heptan-6,7-carbolactone by the action of ammonia and hydrazine and subsequent oxidative cyclization of the resulting hydroxy amide and hydroxy hydrazide gave a cyclic carbamate, 3-oxa-5-azatricyclo[4.4.0.0^{2 , 7}]decan-4-one.     

Synthesis of 5,8-dihydroxynaphtho[2,3-c][1,2,5]thiadiazole-6,9-dione and 6,9-dihydroxybenzo[g]quinoxaline-5,10-dione

The synthesis of 5,8-dihydroxynaphtho[2,3-c][1,2,5]thiadiazole-4,9-dione 3 , 6,9-dihydroxybenzo[g]quinoxaline-5,10-dione 4 , and their lesser oxygenated analogs via Friedel-Crafts and Diels-Alder synthesis is reported.     

The Adamantane Rearrangement of Tricyclo[4.2.2.01,5]decane to Tricyclo[5.3.0.04,8]decane

Regioselective generation of the C(2)-carbocation a of tricyclo[4.2.2.0^1,5]decane ( 1 ) by treatment of both corresponding epimeric alcohols 5 and 6 with BF₃ and trapping the rearranged tricyclo[5.3.0.0^4,8]decan-7-yl carbocation b with Et₃SiH as hydride-ion donor (ionic hydrogenation) gives the corresponding hydrocarbon 3 as sole product in almost quantitative yield. The latter is a known intermediate in the Lewis-acid-catalyzed rearrangement of 1 to adamantane ( 4 ).     

Crystal and molecular structure of 5-ethyl-5,10-dihydrido-10,10-diphenylphenazasiline

The structure of 5-ethyl-5,10-dihydro-10,10-diphenylphenazasiline has been determined from three-dimensional X-ray data collected by counter methods. The compound in the monoclinic space group P2₁/b with a 10.782(5), b 22.642(9), c 8.830(4) Å and γ 74°41′(2). The observed and calculated densities (Z = 4) are 1.22 and 1.21 g cm^-3, respectively. Anisotropic(Si, N, C)-isotropic block-diagonal least squares refinement gave a conventional R factor of 3.9% for 1871 reflections with I>2σ(I). The central six-membered ring of the tricyclic system adopts a boat conformation; the dihedral angle between the benzo-group planes is 157.3°. The CSiC angle in the heterocycle is 101.1(1)°; the mean SiC bond length is 1.850(2) Å (in the cycle) and 1.862(2) Å (with Ph group). The nitrogen atom is displaced 0.05 Å from the plane of the adjacent carbon atoms; the sum of the angle about N is 359.7°.     

Naphthoindazoles. Synthesis of 4,11-Dimethoxynaphtho[2,3-f]indazole-5,10-dione

The previously unknown 4,11-dimethoxynaphtho[2,3-f]indazole-5,10-dione has been obtained by the thermal cyclization of N-nitroso derivative of 2-acetamido-3-methyl-1,4-dimethoxyanthraquinone.     

Long-Lived Carbocations: Generation from 5,5,10,10-Tetramethyl-5,10-dihydroindeno[2,1-a]indene, Structure, and Rearrangements

According to the NMR data, protonation of 5,5,10,10-tetramethyl-5,10-dihydroindeno[2,1-a]indene in the system HSO₃F-SO₂ClF-CD₂Cl₂ at -80°C gives rise to long-lived 5,5,10,10-tetramethyl-2H-5,10-di- hydroindeno[2,1-a]indenium ion which undergoes isomerization into 4b,5,10,10-tetramethyl-4b,5,9b,10-tetra- hydroindeno[2,1-a]inden-5-yl cation on raising the temperature. On the basis of the data obtained for rear- rangements of such carbocations an alternative mechanism has been proposed for the rearrangements of struc- turally related carbocations having a bicyclo[3.3.0]octane skeleton.     

Synthesis of regioisomeric 6,9-(chlorofluoro)-substituted benzo[g]quinoline-5,10-diones,benzo[g] isoquinoline-5,10-diones and 6-chloro-9-fluorobenzo[g]quinoxaline-5,10-dione

Treatment of difluoro or chloro fluoro-substituted benzyl bromides 5a-c with zinc dust in tetrahydro-furan leads to the corresponding benzylic zinc bromides 6a-c. These organometallics on treatment with chlorosubstituted heterocyclic esters 4A and 4B mediated by nickel catalysis undergo couplings to yield dihalobenzyl substituted heterocyclic esters 7Aa-c and 7Ba-c. Treatment of 4c with 6c under Pd catalysis leads to 7Cc. The acids 8, prepared by hydrolysis of these esters, with treatment of fuming sulfuric acid undergo cyclizations and oxidations to yield the desired regioisomeric dihalo-substituted heterocyclic quinones 2.     

Selective synthesis of chiral dioxabicyclo[4.4.0]decane and dioxabicyclo[5.3.0]decane from 3,4-bisallyloxy-but-1-yne derivatives via ruthenium-catalyzed en-yn-ene metathesis

We prepared a series of chiral 3,4-bisallyloxy-but-1-ynes having syn and anti configurations. Treatment of these substrates with Grubbs catalyst Cl2(PCy3)2Ru=CHPh (3 mol %) preferably gave chiral dioxabicyclo[4.4.0]decane (yields > 55%) in addition to dioxabicyclo[5.3.0]decane in minor proportions. On substitution of the 4-allyloxy group of these substrates with a 4-but-2-enyloxy group, the metathesis reactions produced only dioxabicyclo[5.3.0]decane in the presence of Grubbs ruthenium-imidazolidene carbene catalyst.     

Mannich Condensation of exo-2,exo-6-Tricyclo[5.2.1.02,6]decan-8-one

Mannich condensation of exo-2,exo-6-tricyclo[5.2.1.02,6]decan-8-one with paraformaldehyde and dimethylamine hydrochloride results in the addition of dimethylaminomethyl fragment at the C⁹ atom to give the exo-9-isomer. The reaction of exo-9-dimethylaminomethyl-exo-2,exo-6-tricyclo[5.2.1.02,6]decan-8-one with hydroxylamine hydrochloride in alcoholic alkali yields the corresponding Z-oxime which undergoes selective rearrangement into exo-10-dimethylaminomethyl-9-aza-exo-2,exo-6-tricyclo[5.3.1.02,6]undecan-8-one by the action of sulfuric acid in acetonitrile.