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A-indanone

A ketone contained in a five-menibered ring was also employed in these reactions when a-indanone was fused with 194 to give the indeno[3,2-b]quinoline 20 0 345 and with l,3-di-2-naphthyl-2-thiourea to give the indeno[3,2-6]-l-azaphenant.hrene 201. [Pg.149]

Recent work on the thermal indolization of arylhydrazones has introduced new synthetic possibilities for azaindoles. Kelly et al. refluxed cyclohexanone and deoxybenzoin 2-pyridylhydrazones in diethylene glycol to give 5,6,7,8-tetrahydro-a-carboline (42, R = H) and 2,3-diphenyl-7-azaindole in 70 and 56% yields, respectively, compared with 53 and 12% reported earlier. Similarly, y-carboline 29 was obtained in 95 % yield from cyclohexanone 4-pyTidylhydrazone (lit. 48% ). Several 7-azaindole derivatives were prepared in the same manner. The yields ranged from 5 % for azaindolenine (31) to 88% for 3-phenyl-7-azaindole. 3,3-Dimethyl-7-azaindolenine was obtained in 47 % yield from the isobutyralaldehyde hydrazone. The novel cyclic compounds 40 and 41 were obtained from the 2-pyridylhydrazones of cyclopentanone, a-indanone, and a-tetralone in 67, 95, and 77% yields, respectively. Unfortunately, all attempts to cyclize the acetone, pyruvic acid, and ethyl pyruvate hydrazones were unsuccessful. Also, cyclohexanone and methyl ethyl ketone 5-nitro-2-... [Pg.40]

It is well documented that direct complexation of 1-alkylindane or 1-alkyltetrahn with Cr(CO)e produces a mixture of two possible diastereomerie ehromium complexes, endo and exo isomers, and the ratio depends on the steric effect and the nature of the substituents [46]. It might also be possible to synthesize either endo or exo isomers stereoselectively, from a common a-tetralone or a-indanone. [Pg.204]

Scheme 9.13 Asymmetric hydrogenation of cyclic enamides with an endocyclic double bond derived from a tetralone and a indanone. Scheme 9.13 Asymmetric hydrogenation of cyclic enamides with an endocyclic double bond derived from a tetralone and a indanone.
The cyclic a-tetralone sulfene (135) with benzylideneanilines in the presence of triethylamine afforded only the dimer 136, however benzylidenealkylamines gave [4 + 2] cycloadducts 137 (equation 125)73. The chemical behavior of the a-indanone sulfene (138),... [Pg.752]

It is well known that the tricarbonylchromium-complexed benzylic anions and cations are stabilized due to overlapping between d-orbital of the chromium and p-orbital of the benzylic carbon [1]. Tricarbonylchromium complexes of a-te-tralone and a-indanone having a carbonyl group at the side chain underwent a deprotonation of the exo-benzylic protons by treatment with base to give the stereo-controlled tricyclic compounds (Eqs. 1 and 2) [2]. In these cases, Robinson annulation products were formed in less than 10% yield. Also, base treatment of benzyl ether chromium complex having a chlorine at the side chain 3 gave cyclization product as a diastereomeric mixture (Eq. 3) [3]. [Pg.130]

Feng developed an enantioselective Strecker-type reaction of ketimines with trimethylsilylcyanide catalysed by a chiral BINOL-derived sodium phosphate (10 mol%) prepared in situ from 55 and NaH (Scheme 2.35). As a protic additive, 10 mol% of 4-tert-butyl-2-adamantylphenol (56) was effective for improving the yield and enantioselectivity. Both aliphatic and aromatic ketimines, including cyclic ketimines derived from a-indanone and a-tetralone, were used for this reaction. [Pg.33]

Many patents have been issued on the use of pyrogaUol derivatives as pharmaceuticals. PyrogaUol has been used extemaUy in the form of an ointment or a solution in the treatment of skin diseases, eg, psoriasis, ringworm, and lupus erythematosus. GaUamine triethiodide (16) is an important muscle relaxant in surgery it also is used in convulsive-shock therapy. Trimethoprim (2,4-diamino-5-(3,4,5-trimethoxybenzyl)pyrimidine) is an antimicrobial and is a component of Bactrin and Septra. Trimetazidine (l(2,3,4-trimethoxybenzyl)piperazine (Vastarel, Yosimilon) is used as a coronary vasodilator. l,2,3,4-Tetrahydro-6-methoxy-l-(3,4,5-trimethoxyphenyl)-9JT-pyrido[3,4- ]indole hydrochloride is useful as a tranquilizer (52) (see Hypnotics, sedatives, ANTICONVULSANTS, AND ANXIOLYTICS). Substituted indanones made from pyrogaUol trimethyl ether depress the central nervous system (CNS) (53). Tyrosine-and glycine(2,3,4-trihydroxybenzyl)hydrazides are characterized by antidepressant and anti-Parkinson activity (54). [Pg.378]

Dimethoxy-l-indanone [2107-69-9] M 192.2, m 118-120 . Crystd from MeOH, then sublimed in a vacuum. [Pg.210]

Schmidt reaction of indanones 803 by treatment with HN3-BF3 etherate gave 4,5-dihydro[5,l-a]tetrazoloquinoline 804 (92IJC(B)610)) (Scheme 142). [Pg.176]

A rather simple derivative of 1-indanone itself has been reported to possess analgesic activity. This is particularly noteworthy in that this agent, drindene ( ),... [Pg.65]

In order to avoid as far as possible double bond positional isomers, a problem quite common in drugs with indene moieties, N-trityl-2-hydroxymethylmorpholine (23) was reacted with the potassium. salt of 4-hydroxy-1-indanone (24) in DMSO solvent to give condensation product 25 in good yield. Reduction of 25 with LLAIH produced the hydroxyindane which was dehydrated and deprotected with HCl to give indeloxazine (26) [8]. [Pg.59]

The Fries rearrangement can be viewed as a type of Friedel-Crafts acylation reaction. Two examples of this reaction are given in Scheme 5.1-61. The first is the rearrangement of 4,4 -diacetoxybiphenyl to 4,4 -dihydroxy-3,3 -diacetoxybiphenyl in a NaCl/AlCl3 (X(A1C13) = 0.69) molten salt [93]. The second example is the rearrangement of phenyl 3-chloropropionate to 2 -hydroxy-3-chloropropiophenone, followed by cyclization to an indanone [94]. [Pg.204]

When phthalates are added to a solution of sodium methoxide in DMSO 2-(methanesulphinyl)-l,3-indanone 469 is readily formed541 (equation 280). [Pg.338]

In 1986 Yamashida et al. found that the reaction of the (morpholino)phenyl-carbene complex 46 with symmetric alkynes 47 gave the morpholinylindene derivatives 48 and 49, as well as the indanones 50 derived from the latter by hydrolysis, in excellent yields (Scheme 9) [54]. This contrasts with the behavior of the corresponding (methoxy)phenylcarbene complex, which solely undergoes the Dotz reaction [55]. This transformation of the amino-substituted complex 46 apparently does not involve a CO insertion, which is an important feature of the Dotz benzannelation. [Pg.29]

The unconventional structure of fulvenes with a unique C=C bond conjugation leads to unusual cycloaddition reactions with other unsaturated systems. For example, alkenylcarbene complexes react with fulvenes leading to indanone or indene derivatives which can be considered as derived from a [6S+3C] cycloaddition process [118] (Scheme 72). The reaction pathway is well explained by an initial 1,2-addition of the fulvene to the carbene carbon followed by [1,2]-Cr(CO)5-promoted cyclisation. [Pg.107]

Dihydro-1-vinylnaphthalene (67) as well as 3,4-dihydro-2-vinylnaphtha-lene (68) are more reactive than the corresponding aromatic dienes. Therefore they may also undergo cycloaddition reactions with low reactive dienophiles, thus showing a wider range of applications in organic synthesis. The cycloadditions of dienes 67 and 68 and of the 6-methoxy-2,4-dihydro-1-vinylnaphthalene 69 have been used extensively in the synthesis of steroids, heterocyclic compounds and polycyclic aromatic compounds. Some of the reactions of dienes 67-69 are summarized in Schemes 2.24, 2.25 and 2.26. In order to synthesize indeno[c]phenanthrenones, the cycloaddition of diene 67 with 3-bromoindan-l-one, which is a precursor of inden-l-one, was studied. Bromoindanone was prepared by treating commercially available indanone with NBS [64]. [Pg.53]

Scheme 10.3 gives some examples of pinacol and related rearrangements. Entry 1 is a rearrangement done under strongly acidic conditions. The selectivity leading to ring expansion results from the preferential ionization of the diphenylcarbinol group. Entry 2, a preparation of 2-indanone, involves selective ionization at the benzylic alcohol, followed by a hydride shift. [Pg.888]

Another interesting [3+2] cycloaddition in aqueous media was recently reported by Murakami.131 2-Cyanophenylboronic acid reacted as a three-carbon component with alkynes or alkenes to afford substituted indenones or indanones (Eq. 4.67). The use of an alkynoate even produced benzotropone, a formal [3 + 2 + 2] adduct. [Pg.136]

Reaction of p-fluorobenzyl chloride with the anion of diethylmethylmalonate ester followed by saponification and decarboxylation leads to acid 9. Polyphosphoric acid cyclization leads to indanone 10. A Reformatsky reaction with zinc amalgam and bromo-acetic ester leads to carbinol 11 which is then... [Pg.209]

Treatment with triethylsilane and boron trifluoride etherate allows a variety of methyl (i-hydroxy-/3-ary lpropionates to be reduced to methyl ft -ary lpropionates in yields of 85-100% as part of a synthetic sequence leading to the preparation of indanones (Eq. 31).170 Small amounts of dehydration products formed simultaneously are reduced to the methyl -arylpropionates by mild catalytic hydrogenation.170... [Pg.22]

Alkenyl Fischer carbene complexes can serve as three-carbon components in the [6 + 3]-reactions of vinylchro-mium carbenes and fulvenes (Equations (23)—(25)), providing rapid access to indanone and indene structures.132 This reaction tolerates substitution of the fulvene, but the carbene complex requires extended conjugation to a carbonyl or aromatic ring. This reaction is proposed to be initiated by 1,2-addition of the electron-rich fulvene to the chromium carbene followed by a 1,2-shift of the chromium with simultaneous ring closure. Reductive elimination of the chromium metal and elimination/isomerization gives the products (Scheme 41). [Pg.625]


See other pages where A-indanone is mentioned: [Pg.52]    [Pg.291]    [Pg.291]    [Pg.238]    [Pg.27]    [Pg.71]    [Pg.456]    [Pg.52]    [Pg.291]    [Pg.291]    [Pg.238]    [Pg.27]    [Pg.71]    [Pg.456]    [Pg.373]    [Pg.124]    [Pg.215]    [Pg.58]    [Pg.46]    [Pg.75]    [Pg.227]    [Pg.2396]    [Pg.278]    [Pg.307]    [Pg.460]    [Pg.93]    [Pg.177]    [Pg.139]    [Pg.245]    [Pg.187]    [Pg.27]    [Pg.50]   
See also in sourсe #XX -- [ Pg.35 ]




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