Synthesis of fluoride garnets {Na3}[M3+2](Li3)F12 (M = Al,Cr, and Fe) from aqueous solution and their properties

The garnet-type fluorides, Na₃M₂Li₃F₁₂ (M = Al, Cr, and Fe) were synthesized as the coprecipitates of ～1 to 10 μm powders from HF solutions. The garnet structures were always obtained under acidic conditions. The incorporation of water molecules into the structure of the Cr and Fe garnets was observed. After heat treatment at 300°C, very small unknown peaks were observed in the X-ray powder pattern in addition to the garnet phase which had a slightly smaller value of the lattice constant than that of hydrous garnets. From the measurement of magnetic properties and Mössbauer effects, the Fe and Cr garnets were found to be paramagnetic with both ions in the trivalent state. Presentation of infrared spectra of the garnets is also included.     

Reactions of oxalyl chloride with 1,2-cycloalkanediols in the presence of triethylamine

The relationship between the product patterns and the configurations of 1,2-cycloheptane- and 1,2-cyclooctanediols 9 in the cyclocondensations with oxalyl chloride in the presence of triethylamine at 0 degrees C has been shown analogous to that obtained for 1,2-disubstituted acyclic ethylene glycols 1: cis-1,2-cyclooctanediol (9f) produced the cyclic oxalate 14f as the major product, while trans-1,2-cycloheptanediol (9e) and trans-1,2-cyclooctanediol (9g) formed the cyclic carbonates 12e, g as the major products. On the other hand, the cyclic oxalates 14a-d were formed as the major products from 1,2-cyclopentane- and 1,2-cyclohexanediols regardless of the configuration. These results can be accounted for by assuming the boat-like transition states for cyclizations of the half esters of comparatively rigid five- and six-membered diols 9a--d. The cyclic oxalates 14a, c may be directly formed through the resulting tetrahedral intermediates from cis-diols (9a,c), and the cyclic carbonates 12a,c as the minor products after ring inversion of the tetrahedral intermediates. The tetrahedral intermediates from the trans-isomers 9b, d cannot undergo ring inversion, producing no traces of the cyclic carbonates 12b, d.     

Structure and dioxygen-reactivity of copper(I) complexes supported by bis(6-methylpyridin-2-ylmethyl)amine tridentate ligands

The structure and dioxygen-reactivity of copper(I) complexes R supported by N,N-bis(6-methylpyridin-2-ylmethyl)amine tridentate ligands L2R[R (N-alkyl substituent)=-CH2Ph (Bn), -CH2CH2Ph (Phe) and -CH2CHPh2(PhePh)] have been examined and compared with those of copper(I) complex (Phe) of N,N-bis[2-(pyridin-2-yl)ethyl]amine tridentate ligand L1(Phe) and copper(I) complex (Phe) of N,N-bis(pyridin-2-ylmethyl)amine tridentate ligand L3(Phe). Copper(I) complexes (Phe) and (PhePh) exhibited a distorted trigonal pyramidal structure involving a d-pi interaction with an eta1-binding mode between the metal ion and one of the ortho-carbon atoms of the phenyl group of the N-alkyl substituent [-CH2CH2Ph (Phe) and -CH2CHPh2(PhePh)]. The strength of the d-pi interaction in (Phe) and (PhePh) was weaker than that of the d-pi interaction with an eta2-binding mode in (Phe) but stronger than that of the eta1 d-pi interaction in (Phe). Existence of a weak d-pi interaction in (Bn) in solution was also explored, but its binding mode was not clear. Redox potentials of the copper(I) complexes (E1/2) were also affected by the supporting ligand; the order of E1/2 was Phe>R>Phe. Thus, the order of electron-donor ability of the ligand is L1Phe相似文献   

Synthesis of Optically Active P‐Chiral and Optically Inactive Oligophosphines

A series of optically active P‐chiral oligophosphines (S,R,R,S)‐ 2 , (S,R,S,S,R,S)‐ 3 , (S,R,S,R,R,S,R,S)‐ 4 , and (S,R,S,R,S,R,R,S,R,S,R,S)‐ 5 with four, six, eight, and 12 chiral phosphorus atoms, respectively, were successfully synthesized by a step‐by‐step oxidative‐coupling reaction from (S,S)‐ 1 . The corresponding optically inactive oligophosphines 1′ – 5′ were also prepared. Their properties were characterized by DSC, XRD, and optical‐rotation analyses. While optically active bisphosphine (S,S)‐ 1 and tetraphosphine (S,R,R,S)‐ 2 behaved as small molecules, octaphosphine (S,R,S,R,R,S,R,S)‐ 4 and dodecaphosphine (S,R,S,R,S,R,R,S,R,S,R,S)‐ 5 exhibited the features of a polymer. Furthermore, DSC and XRD analyses showed that hexaphosphine (S,R,S,S,R,S)‐ 3 is an intermediate between a small molecule and a polymer. Comparison of optically active oligophosphines 1 – 5 with the corresponding optically inactive oligophosphines 1′ – 5′ revealed that the optically active phosphines have higher crystallinity than the optically inactive counterparts. It is considered that the properties of oligophosphines depend on the enantiomeric purity as well as the oligomer chain length.     

CO2 laser Stark spectroscopy of the Coriolis-coupled ν2 and ν5 bands of CD3Br

The ν₂ (CD₃ symmetrical deformation) and ν₅ (CD₃ degenerate deformation) fundamental bands of CD₃Br were studied by 9.4- and 10.4-μm CO₂ laser Stark spectroscopy. Stark resonances originating from 28 and 53 rovibrational transitions of the ν₂ and ν₅ bands, respectively, were assigned for each of the isotopic species, CD₃⁷⁹Br and CD₃⁸¹Br. These two bands were simultaneously analyzed with explicit inclusion of the ν₂-ν₅ Coriolis interaction, yielding precise molecular constants in the ν₂ and ν₅ excited states as well as the Coriolis coupling constant. The molecular constants obtained are consistent between the two isotopic species and are in good agreement with the results of high-resolution infrared studies. The band origins and dipole moments are

     

26.

Alkyl Ammonium Ion Selectivity of Hexahomotrioxacalix[3]arene Triamide Derivative having the Intramolecular Hydrogen-Bonding Group     

Takehiko Yamato  Fumika Kitajima  Jeong Tae Gil 《Journal of inclusion phenomena and macrocyclic chemistry》2005,53(3):257-262

The lower rim functionalized hexahomotrioxacalix[3]arene triamide 4 with cone-conformation was synthesized from triol 1 by a stepwise reaction. The different extractability for alkali metal ions, transition metal ions, and alkyl ammonium ions from water into dichloromethane is discussed. Due to the strong intramolecular hydrogen bonding between the neighboring NH and CO groups in triamide 4, its affinity to metal cations was weakened. Triamide 4 shows a single selectivity to n-BuNH₃⁺. The anion complexation of triamide 4 was also studied by ¹H NMR titration experiments. Triamide 4 binds halides through the intermolecular hydrogen bonding among the NH hydrogens of amide in a 1:1 fashion in CDCl₃. The association constants calculated from these changes in chemical shifts of the amide protons are K_a = 223 M⁻¹ for Cl⁻ and K_a = 71.7 M⁻¹ for Br⁻. Triamide 4 shows a preference for Cl⁻ complexation than Br⁻ complexation.     

27.

Synthesis of Indolones via Radical Cyclization of N‐(2‐Halogenoalkanoyl)‐Substituted Anilines     

Takehiko Nishio  Kyoko Iseki  Norihito Araki  Takenori Miyazaki 《Helvetica chimica acta》2005,88(1):35-41

The radical reactions of N‐(2‐halogenoalkanoyl)‐substituted anilines (anilides) of type 1 have been investigated under various conditions. Treatment of compounds 1a – 1o with Bu₃SnH in the presence of (2,2′‐azobis(isobutyronitrile) (AIBN) afforded a mixture of the indolones (oxindoles) 2a – 2o and the reduction products 5a – 5o (Table 1). In contrast, the N‐unsubstituted anilides 1p – 1s, 1u , and 1v gave the corresponding reduction products exclusively (Table 1). Similar results were obtained by treatment of 1 with Ni powder (Table 2) or wth Et₃B (Table 3). Anilides with longer N‐(phenylalkyl) chains such as 6 and 7 were inert towards radical cyclization, with the exception of N‐benzyl‐2‐bromo‐N,2‐dimethylpropanamide ( 6b ), which, upon treatment with Ni powder in i‐PrOH, afforded the cyclized product 9b in low yield (Table 4). Upon irradiation, the extended anilides 6, 7, 10 , and 11 yielded the corresponding dehydrobromination products exclusively (Table 5).     

28.

Synthesis of 2-, 4- and 5-(2-alkylcarbamoyl-1-methylvinyl)-7-alkyloxybenzo[b]furans and their leukotriene B4 receptor antagonistic activity     

Ando K  Tsuji E  Ando Y  Kunitomo J  Kobayashi R  Yokomizo T  Shimizu T  Yamashita M  Ohta S  Nabe T  Kohno S  Ohishi Y 《Organic & biomolecular chemistry》2005,3(11):2129-2139

Variable benzo[b]furan derivatives having (E)- and (Z)-2-alkylcarbamoyl-1-methylvinyl groups at the 2-, 4- and 5-positions and a carboxylpropoxy or (1-phenyl)ethoxy group at the 7-position were prepared to find novel and selective leukotriene B4(LTB4) receptor antagonists. (E)-2-(2-diethylcarbamoyl-1-methylvinyl)-7-(1-phenylethoxy)benzo[b]furan (4v) showed selective inhibition to the human BLT2 receptor (hBLT2). On the other hand, (E)-2-acetyl-4-(2-diethylcarbamoyl-1-methylvinyl)-7-(1-phenylethoxy)benzo[b]furan (7v) inhibited both human BLT(1) receptor (hBLT1) and hBLT2. The (E)-2-(2-diethylcarbamoyl-1-methylvinyl) group lay on approximately the same plane as the benzo[b]furan ring, whereas the (E)-4-(2-diethylcarbamoyl-1-methylvinyl) group had the torsion angle (45.7 degree) from the benzo[b]furan ring plane. However, the (Z)-(2-alkylcarbamoyl-1-methylvinyl)benzo[b]furans were inactive. The inhibitory activity depended on the conformation of the 2-diethylcarbamoyl-1-methylvinyl group.     

29.

Practical synthesis of a neuropeptide Y antagonist via stereoselective addition to a ketene     

Iida T  Satoh H  Maeda K  Yamamoto Y  Asakawa K  Sawada N  Wada T  Kadowaki C  Itoh T  Mase T  Weissman SA  Tschaen D  Krska S  Volante RP 《The Journal of organic chemistry》2005,70(23):9222-9229

[Reaction: see text]. The synthesis of neuropeptide Y antagonist 1, currently under clinical investigation for the treatment of obesity, is described. The convergent synthesis from trans-spirolactone carboxylic acid intermediate 2a and aminopyrazole 3 is predicated on a stereoselective route to the former. The coupling reaction of ethyl 4-oxocyclohexanecarboxylate (10a) with lithiated isonicotinamide 11 was investigated in detail, but even optimized conditions only provided a 45:55 ratio of trans:cis isomers (12a:12b). While selective crystallization schemes were developed to isolate the thermodynamically less stable trans isomer 2a, improved stereocontrol was subsequentially achieved by the application of ketene chemistry. The ketene formation and quench was investigated under a variety of conditions aimed at maximizing the trans:cis ratio. Reacting a mixture of carboxylic acids 2a and 2b with POCl3 in THF, followed by concomitant addition of tert-butyl alcohol in the presence of TMEDA at 35 degrees C provided a 4:1 ratio of trans:cis tert-butyl esters (18a:18b) via in situ ketene formation. Ester hydrolysis, followed by selective crystallization of undesired 2b as the HCl salt, led to isolation of 2a in 47% overall yield. Aminopyrazole intermediate 3 was synthesized via the condensation reaction of 2-fluorophenylhydrazine hydrochloride (4a) with acrylonitrile derivative 5 in 65-70% yield. Coupling of advanced intermediates 2a and 3b via activation with thionyl chloride gave a 92% yield of 1.     

30.

An efficient novel synthesis of beta-(azuleno[1,2-b]benzothienyl)- and beta-(azuleno[2,1-b]benzothienyl)-alpha,beta-unsaturated ketones by the tropylium ion-mediated intramolecular furan ring-opening reaction and X-ray investigation of methyl ketone derivative     

Yamamura K  Houda Y  Hashimoto M  Kimura T  Kamezawa M  Otani T 《Organic & biomolecular chemistry》2004,2(9):1413-1418

Intramolecular reaction of 2-tropylio-3-(5-substituted 2-furyl)benzothiophenes (3), prepared from the corresponding 2-cycloheptatrienyl-3-(5-substituted 2-furyl)benzothiophenes (2), afforded the beta-(azuleno[1,2-b]benzothienyl)-alpha,beta-unsaturated ketones (4), which are otherwise difficult to obtain, in moderate yields. The reaction involves a ring-opening process of the furan ring by intramolecular attack of the tropylium ion onto the 2-position of the furan ring. Similarly, beta-(azuleno[2,1-b]benzothienyl)-alpha,beta-unsaturated ketones (8) were obtained from the corresponding 3-tropylio-2-(5-substituted 2-furyl)benzothiophenes (7) albeit in lower yields. The molecular and crystal structures of the methyl ketone derivative, 8a, are discussed on the basis of X-ray structure analysis.     

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		CD379Br		CD381Br
$\text{ν}{}_2$		991.396 82 (18)		991.388 46 (17)		cm?1
$\text{ν}{}_5$		1055.469 00 (12)		1055.466 32 (12)		cm?1
$\text{μ}{}_0$		1.830 42 (52)		1.829 84 (47)		D
$\text{μ}{}_2$		1.829 93 (48)		1.829 57 (46)		D
$\text{μ}{}_5$		1.832 23 (60)		1.831 19 (56)		D

Alkyl Ammonium Ion Selectivity of Hexahomotrioxacalix[3]arene Triamide Derivative having the Intramolecular Hydrogen-Bonding Group

The lower rim functionalized hexahomotrioxacalix[3]arene triamide 4 with cone-conformation was synthesized from triol 1 by a stepwise reaction. The different extractability for alkali metal ions, transition metal ions, and alkyl ammonium ions from water into dichloromethane is discussed. Due to the strong intramolecular hydrogen bonding between the neighboring NH and CO groups in triamide 4, its affinity to metal cations was weakened. Triamide 4 shows a single selectivity to n-BuNH₃⁺. The anion complexation of triamide 4 was also studied by ¹H NMR titration experiments. Triamide 4 binds halides through the intermolecular hydrogen bonding among the NH hydrogens of amide in a 1:1 fashion in CDCl₃. The association constants calculated from these changes in chemical shifts of the amide protons are K_a = 223 M⁻¹ for Cl⁻ and K_a = 71.7 M⁻¹ for Br⁻. Triamide 4 shows a preference for Cl⁻ complexation than Br⁻ complexation.     

Synthesis of Indolones via Radical Cyclization of N‐(2‐Halogenoalkanoyl)‐Substituted Anilines

The radical reactions of N‐(2‐halogenoalkanoyl)‐substituted anilines (anilides) of type 1 have been investigated under various conditions. Treatment of compounds 1a – 1o with Bu₃SnH in the presence of (2,2′‐azobis(isobutyronitrile) (AIBN) afforded a mixture of the indolones (oxindoles) 2a – 2o and the reduction products 5a – 5o (Table 1). In contrast, the N‐unsubstituted anilides 1p – 1s, 1u , and 1v gave the corresponding reduction products exclusively (Table 1). Similar results were obtained by treatment of 1 with Ni powder (Table 2) or wth Et₃B (Table 3). Anilides with longer N‐(phenylalkyl) chains such as 6 and 7 were inert towards radical cyclization, with the exception of N‐benzyl‐2‐bromo‐N,2‐dimethylpropanamide ( 6b ), which, upon treatment with Ni powder in i‐PrOH, afforded the cyclized product 9b in low yield (Table 4). Upon irradiation, the extended anilides 6, 7, 10 , and 11 yielded the corresponding dehydrobromination products exclusively (Table 5).     

Synthesis of 2-, 4- and 5-(2-alkylcarbamoyl-1-methylvinyl)-7-alkyloxybenzo[b]furans and their leukotriene B4 receptor antagonistic activity

Variable benzo[b]furan derivatives having (E)- and (Z)-2-alkylcarbamoyl-1-methylvinyl groups at the 2-, 4- and 5-positions and a carboxylpropoxy or (1-phenyl)ethoxy group at the 7-position were prepared to find novel and selective leukotriene B4(LTB4) receptor antagonists. (E)-2-(2-diethylcarbamoyl-1-methylvinyl)-7-(1-phenylethoxy)benzo[b]furan (4v) showed selective inhibition to the human BLT2 receptor (hBLT2). On the other hand, (E)-2-acetyl-4-(2-diethylcarbamoyl-1-methylvinyl)-7-(1-phenylethoxy)benzo[b]furan (7v) inhibited both human BLT(1) receptor (hBLT1) and hBLT2. The (E)-2-(2-diethylcarbamoyl-1-methylvinyl) group lay on approximately the same plane as the benzo[b]furan ring, whereas the (E)-4-(2-diethylcarbamoyl-1-methylvinyl) group had the torsion angle (45.7 degree) from the benzo[b]furan ring plane. However, the (Z)-(2-alkylcarbamoyl-1-methylvinyl)benzo[b]furans were inactive. The inhibitory activity depended on the conformation of the 2-diethylcarbamoyl-1-methylvinyl group.     

Practical synthesis of a neuropeptide Y antagonist via stereoselective addition to a ketene

[Reaction: see text]. The synthesis of neuropeptide Y antagonist 1, currently under clinical investigation for the treatment of obesity, is described. The convergent synthesis from trans-spirolactone carboxylic acid intermediate 2a and aminopyrazole 3 is predicated on a stereoselective route to the former. The coupling reaction of ethyl 4-oxocyclohexanecarboxylate (10a) with lithiated isonicotinamide 11 was investigated in detail, but even optimized conditions only provided a 45:55 ratio of trans:cis isomers (12a:12b). While selective crystallization schemes were developed to isolate the thermodynamically less stable trans isomer 2a, improved stereocontrol was subsequentially achieved by the application of ketene chemistry. The ketene formation and quench was investigated under a variety of conditions aimed at maximizing the trans:cis ratio. Reacting a mixture of carboxylic acids 2a and 2b with POCl3 in THF, followed by concomitant addition of tert-butyl alcohol in the presence of TMEDA at 35 degrees C provided a 4:1 ratio of trans:cis tert-butyl esters (18a:18b) via in situ ketene formation. Ester hydrolysis, followed by selective crystallization of undesired 2b as the HCl salt, led to isolation of 2a in 47% overall yield. Aminopyrazole intermediate 3 was synthesized via the condensation reaction of 2-fluorophenylhydrazine hydrochloride (4a) with acrylonitrile derivative 5 in 65-70% yield. Coupling of advanced intermediates 2a and 3b via activation with thionyl chloride gave a 92% yield of 1.     

An efficient novel synthesis of beta-(azuleno[1,2-b]benzothienyl)- and beta-(azuleno[2,1-b]benzothienyl)-alpha,beta-unsaturated ketones by the tropylium ion-mediated intramolecular furan ring-opening reaction and X-ray investigation of methyl ketone derivative

Intramolecular reaction of 2-tropylio-3-(5-substituted 2-furyl)benzothiophenes (3), prepared from the corresponding 2-cycloheptatrienyl-3-(5-substituted 2-furyl)benzothiophenes (2), afforded the beta-(azuleno[1,2-b]benzothienyl)-alpha,beta-unsaturated ketones (4), which are otherwise difficult to obtain, in moderate yields. The reaction involves a ring-opening process of the furan ring by intramolecular attack of the tropylium ion onto the 2-position of the furan ring. Similarly, beta-(azuleno[2,1-b]benzothienyl)-alpha,beta-unsaturated ketones (8) were obtained from the corresponding 3-tropylio-2-(5-substituted 2-furyl)benzothiophenes (7) albeit in lower yields. The molecular and crystal structures of the methyl ketone derivative, 8a, are discussed on the basis of X-ray structure analysis.