Ferrocene compounds. XXXVIII. Di­methyl ferrocene‐1,1′‐di­carboxyl­ate

In the title compound, [Fe(C₇H₇O₂)₂], the cyclo­penta­dienyl rings and the two attached methoxy­carbonyl groups, in an anti arrangement, form an extended π‐conjugated system. The Fe—C distances range from 2.035 (3) to 2.061 (3) Å and the average value of the C—C bond lengths in the two cyclo­penta­dienyl rings is 1.419 (5) Å. The rings are almost parallel to one another [1.0 (2)°] and are mutually twisted from an eclipsed conformation by only 1.8 (3)° (average value). The methoxy­carbonyl groups are twisted out of the plane of the cyclo­penta­dienyl rings by 6.5 (4) and 15.7 (4)°, respectively. The mol­ecules are joined into dimers by intermolecular C—H⃛O hydrogen bonds that form ten‐membered rings. The same types of hydrogen bonds form eight‐membered rings and infinite chains along the b axis.     

Ferrocene compounds: methyl 1′‐aminoferrocene‐1‐carboxylate

The title compund, [Fe(C₅H₆N)(C₇H₇O₂)], features one strong intermolecular hydrogen bond of the type N—H...O=C [N...O = 3.028 (2) Å] between the amine group and the carbonyl group of a neighbouring molecule, and vice versa, to form a centrosymmetric dimer. Furthermore, the carbonyl group acts as a double H‐atom acceptor in the formation of a second, weaker, hydrogen bond of the type C—H...O=C [C...O = 3.283 (2) Å] with the methyl group of the ester group of a second neighbouring molecule at (x, −y − , z − ). The methyl group also acts as a weak hydrogen‐bond donor, symmetry‐related to the latter described C—H...O=C interaction, to a third molecule at (x, −y − , z + ) to form a two‐dimensional network. The cyclopentadienyl rings of the ferrocene unit are parallel to each other within 0.33 (3)° and show an almost eclipsed 1,1′‐conformation, with a relative twist angle of 9.32 (12)°. The ester group is twisted slightly [11.33 (8)°] relative to the cylopentadienyl plane due to the above‐mentioned intermolecular hydrogen bonds of the carbonyl group. The N atom shows pyramidal coordination geometry, with the sum of the X—N—Y angles being 340 (3)°.     

N,N′‐Bis(2‐pyridylmeth­yl)ferrocene‐1,1′‐diyldicarboxamide and N,N′‐bis­(3‐pyridylmeth­yl)ferrocene‐1,1′‐diyldicarboxamide

The mol­ecules of N,N′‐bis­(2‐pyridylmeth­yl)ferrocene‐1,1′‐diyl­dicarboxamide, [Fe(C₁₂H₁₁N₂O)₂], contain intra­molecular N—H⋯N hydrogen bonds and are linked into sheets by three independent C—H⋯O hydrogen bonds. The mol­ecules of the isomeric compound N,N′‐bis­(3‐pyridylmeth­yl)ferrocene‐1,1′‐diyldicarboxamide lie across inversion centres, and the mol­ecules are linked into sheets by a combination of N—H⋯N hydrogen bonds and π–π stacking inter­actions between pyridyl groups.     

Green Synthesis of 1‐(1,2,4‐Triazol‐4‐yl)spiro[azetidine‐2,3′‐(3H)indole]‐2′,4′(1′H)‐diones as Potential Insecticidal Agents

One pot green synthesis of 1‐(1,2,4‐triazol‐4‐yl)spiro[azetidine‐2,3′‐(3H)‐indole]‐2′,4′(1′H)‐diones was carried out by the reaction of indole‐2,3‐diones,4‐amino‐4H‐1,2,4‐triazole and acetyl chloride/chloroacetyl chloride in ionic liquid [bmim]PF₆ with/without using a catalyst. It was also prepared by conventional method via Schiff's bases, 3‐[4H‐1,2,4‐triazol‐4‐yl]imino‐indol‐2‐one. Further, the corresponding phenoxy derivatives were obtained by the reaction of chloro group attached to azetidine ring with phenols. The synthesized compounds were characterized by analytical and spectral (IR, ¹H NMR, ¹³C NMR, and FAB mass) data. Evaluation for insecticidal activity against Periplaneta americana exhibited promising results.     

Synthesis of (R)‐3‐(tert‐Butoxycarbonylamino)‐4‐(2,4,5‐trifluorophenyl)butanoic Acid,a Key Intermediate,and the Formal Synthesis of Sitagliptin Phosphate

An alternate formal synthesis of Sitagliptin phosphate is disclosed from 2,4,5‐trifluorobenzadehyde in 8 linear steps with an overall yield of 31%. The chiral β‐amino acid moiety present in sitaglitpin is installed via an asymmetric hydrogenation followed by a stereoselective Hofmann rearrangement as the key steps. The key chiral intermediate Boc‐amino acid 1 prepared by this novel route was further converted to Sitagliptin phosphate following the known literature protocol.     

Supramolecular architectures in the salt trimethoprimium ferrocene‐1‐carboxylate and the cocrystal 4‐amino‐5‐chloro‐2,6‐dimethylpyrimidine–ferrocene‐1‐carboxylic acid (1/1)

In the salt trimethoprimium ferrocenecarboxylate [systematic name: 2,4‐diamino‐5‐(3,4,5‐trimethoxybenzyl)pyrimidin‐1‐ium ferrocene‐1‐carboxylate], (C₁₄H₁₉N₄O₃)[Fe(C₅H₅)(C₆H₄O₂)], (I), of the antibacterial compound trimethoprim, the carboxylate group interacts with the protonated aminopyrimidine group of trimethoprim via two N—H…O hydrogen bonds, generating a robust R ₂²(8) ring motif (heterosynthon). However, in the cocrystal 4‐amino‐5‐chloro‐2,6‐dimethylpyrimidine–ferrocene‐1‐carboxylic acid (1/1), [Fe(C₅H₅)(C₆H₅O₂)]·C₆H₈ClN₃, (II), the carboxyl–aminopyrimidine interaction [R ₂²(8) motif] is absent. The carboxyl group interacts with the pyrimidine ring via a single O—H…N hydrogen bond. The pyrimidine rings, however, form base pairs via a pair of N—H…N hydrogen bonds, generating an R ₂²(8) supramolecular homosynthon. In salt (I), the unsubstituted cyclopentadienyl ring is disordered over two positions, with a refined site‐occupation ratio of 0.573 (10):0.427 (10). In this study, the two five‐membered cyclopentadienyl (Cp) rings of ferrocene are in a staggered conformation, as is evident from the C…Cg …Cg …C pseudo‐torsion angles, which are in the range 36.13–37.53° for (I) and 22.58–23.46° for (II). Regarding the Cp ring of the minor component in salt (I), the geometry of the ferrocene ring is in an eclipsed conformation, as is evident from the C…Cg …Cg …C pseudo‐torsion angles, which are in the range 79.26–80.94°. Both crystal structures are further stabilized by weak π–π interactions.     

Synthesis of 2‐(sulfamoylphenyl)‐4′‐(iminoaryl/hetroaryl)‐4‐(4′′‐hydroxyphenyl)‐thiazoles and their O‐glucosides

In continuation of our work, we synthesized 2‐(sulfamoylphenyl)‐4′‐amino‐4‐(4″‐hydroxyphenyl)‐thiazole ( 3a ), which were reacted with various (aryl/hetroaryl) aldehyde to form 2‐(sulfamoylphenyl)‐4′‐(iminoaryl/hetroaryl)‐4‐(4″‐hydroxyphenyl)‐thiazoles ( 4a , 4b , 4c , 4d , 4e , 4f ). Glucosylation of compounds ( 4a , 4b , 4c , 4d , 4e , 4f ) have been done by using acetobromoglucose as a glucosyl donor to afford 2‐(sulfamoylphenyl)‐4′‐(iminoaryl/hetroaryl)‐4‐(2,3,4,6‐tetra‐O‐acetyl‐4″‐O‐β‐D ‐glucosidoxyphenyl)‐thiazoles ( 5a , 5b , 5c , 5d , 5e , 5f ), further on deacetylation to produce 2‐(sulfamoylphenyl)‐4′‐(iminoaryl/hetroaryl)‐4‐(4″‐O‐β‐D ‐glucosidoxyphenyl)‐thiazoles ( 6a , 6b , 6c , 6d , 6e , 6f ). The compounds are confirmed by FTIR, ¹H‐NMR, ¹³C‐NMR, and ES‐Mass spectral analysis. J. Heterocyclic Chem., (2011).     

Enzymatic Synthesis of Nucleoside‐5′‐O‐(1‐thiophosphates) and (SP)‐Adenosine‐5′‐O‐(1‐thiotriphosphate)

Treatment of adenosine with PSCl₃ in trimethyl phosphate gave, after ion‐exchange chromatography, adenosine‐5′‐O‐monophosphate (AMP; 28%) and adenosine‐5′‐O‐monothiophosphate (AMPS; 48%). AMPS was studied as a thiophosphate residue donor in an enzymatic transphosphorylation with nucleoside phosphotransferase (NPase) of the whole cells of Erwinia herbicola. As exemplified by a number of natural and sugar‐ and base‐modified nucleosides, it was demonstrated that NPase of the whole cells of Erwinia herbicola catalyzes the transfer of both thiophosphate and phosphate residues with a similar efficiency. An incubation of AMPS in a phosphorylating extract of Saccharomyces cerevisiae (K‐phosphate buffer (0.3 M , pH 7.0); 3% glucose; 15 mM MgCl₂; 28°, 8 h), followed by ion‐exchange column chromatography afforded AMP (8%), AMPS (recovered, 23%), ATP (11%), and (S_P)‐adenosine‐5′‐O‐(1‐thiotriphosphate) ((S_P)‐ATPαS); (total yield 37%; 48% based on the consumed AMPS). For comparison of physicochemical properties, adenosine was chemically transformed into ATPαS as a mixture of the (S_P) (53%) and (R_P) (44%) diastereoisomers.     

NMR analysis of 6‐(2′,3′‐dihydro‐1′H‐inden‐1′‐yl)‐1H‐indene

¹H, ¹³C and two‐dimensional NMR analyses were applied to determine the NMR parameters of 6‐(2′,3′‐dihydro‐1′H‐inden‐1′‐yl)‐1H‐indene. The measurements were accomplished with 0.5 mg of the substance, this quantity being sufficient to determine the chemical shifts of all the H and C atoms, and also the appropriate coupling constants and to give the complete NMR resonance assignments of the molecule. The predicted patterns of the four different H atoms of the methylene groups of the indane structural element coincided completely with the complex patterns in the NMR spectra. Copyright © 2002 John Wiley & Sons, Ltd.     

Phosphonylmethylaminocyclopentane‐1‐carboxylic acid

Phosphonylmethylaminocyclopentane‐1‐carboxylic acid was synthesized using Kabachnik–Fields reaction conditions in high yield and was characterized by NMR (¹H, ³¹P, and ¹³C) and FAB spectroscopy. © 2003 Wiley Periodicals, Inc. Heteroatom Chem 14:229–230, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.10124     

Hydro­gen‐bonded adducts of ferrocene‐1,1′‐diyl­bis­(di­phenyl­methanol): a finite cyclic 1:1 adduct with 2,2′‐dipyridyl­amine

In ferrocene‐1,1′‐diyl­bis­(di­phenyl­methanol)–2,2′‐dipyridyl­amine (1/1), [Fe(C₁₈H₁₅O)₂]·C₁₀H₉N₃, (I), there is an intramolecular O—H?O hydrogen bond [H?O 2.03 Å, O?O 2.775 (2) Å and O—H?O 147°] in the ferrocenediol component, and the two neutral molecular components are linked by one O—H?N hydrogen bond [H?N 1.96 Å, O?N 2.755 (2) Å and O—H?N, 157°] and one N—H?O hydrogen bond [H?O 2.26 Å, N?O 3.112 (2) Å and N—H?O 164°] forming a cyclic R(8) motif. One of the pyridyl N atoms plays no part in the intermolecular hydrogen bonding, but participates in a short intramolecular C—H?N contact [H?N 2.31 Å, C?N 2.922 (2) Å and C—H?N 122°].     

5,5′‐Di‐tert‐butyl‐2,2′‐di­hydroxy‐3,3′‐methyl­enedibenz­aldehyde and 6,6′‐di‐tert‐butyl‐8,8′‐methyl­ene­bis­(spiro­[4H‐1,3‐benzodioxin‐2,1′‐cyclo­hexane])

Two related compounds containing p‐tert‐butyl‐o‐methyl­ene‐linked phenol or phenol‐derived subunits are described, namely 5,5′‐di‐tert‐butyl‐2,2′‐di­hydroxy‐3,3′‐methyl­ene­di­benz­aldehyde, C₂₃H₂₈O₄, (I), and 6,6′‐di‐tert‐butyl‐8,8′‐methyl­ene­bis­(spiro­[4H‐1,3‐benzo­di­oxin‐2,1′‐cyclo­hexane]), C₃₅H₄₈O₄, (II). Both compounds adopt a `butterfly' shape, with the two phenol or phenol‐derived O atoms in distal positions. Phenol and aldehyde groups in (I) are involved in intramolecular hydrogen bonds and the two dioxin rings in (II) are in distorted half‐chair conformations.     

Metallation reactions. XXXIV. Synthesis of 2‐(1‐hydroxy‐1‐arylethyl)‐1,3‐benzoxathiol‐3‐oxide derivatives

The reaction of benzoxathiole‐3‐oxide with lithiumdiisopropylamide in tetrahydrofuran gave an anion, which was reacted with various aryl‐methyl‐ketones to give 2‐(1‐hydroxy‐1‐arylethyl)‐1,3‐benzoxathiol‐3‐oxide derivatives. The reaction was carried out in different temperature conditions: at ‐88 °C the trans addition stereoisomers to the sulfoxide oxygen atom were the main products.     

Synthesis of 2,2′‐(p‐phenylene)bisbenzazoles compounds from terephthalohydroxamoyl chloride

In this study, synthesis of symmetric compounds of 2,2′‐(p‐phenylene)bisbenzothiazole, 2,2′‐(p‐phenyl‐ene)bisbenzimidazole and 5,5′‐dimethyl‐2,2′‐(p‐phenylene)bisbenzoxazole were benefited from the reaction of terephthalohydroxamoyl chloride with 2‐amino‐4‐methyl phenol, o‐aminothio phenol and o‐phenylenedi‐amin compounds. The structures of these compounds were confirmed by elemental analysis, mass, ¹H‐NMR and FT‐IR techniques.     

1,1′‐(Ethenyl­idene)bis­(4‐chloro­benzene)

The title compound, C₁₄H₁₀Cl₂, crystallizes as colourless prisms with two symmetry‐independent mol­ecules in the unit cell. Numerous inter­molecular C—H⋯π inter­actions dominate in the crystal structure, where C—H⋯Cl and long Cl⋯Cl contacts are also observed.     

4′‐[2‐(2‐Ethoxyethoxy)ethoxy]biphenyl‐4‐carboxylic acid: correlation between its crystalline and smectic phases

The crystal structure of the dimeric title compound, C₁₉H₂₂O₅, is dominated by a head‐to‐head hydrogen‐bonding interaction between centrosymmetrically related carboxyl groups in each monomer. The result is a dimeric axis of unusual length (ca 34 Å), but still shorter than what could be expected for a fully extended chain, owing to two turning points in the oligoethoxy ends. This allows for an explanation of the structure of the smectic mesophase exhibited by this compound and at the same time fully validates former geometric estimations based on PM3 calculations.