Stereoselective Methylation of 1-(Diphenylphosphanyl)-2-[(methoxycarbonyl)methyl]ferrocene. The Crystal Structures of the Methylated Ester and Its Palladium(II) Complex with an Auxiliary 2-[(Dimethylamino)methyl]phenyl Ligand.

2007 ◽  
Vol 72 (8) ◽  
pp. 985-995 ◽  
Author(s):  
Martin Lamač ◽  
Ivana Císařová ◽  
Petr Štěpnička

Treatment of racemic 1-(diphenylphosphanyl)-2-[(methoxycarbonyl)methyl]ferrocene successively with NaN(SiMe3)2 and methyl iodide affords the C-alkylated product, 1-(diphenylphosphanyl)-2-[1-(methoxycarbonyl)ethyl]ferrocene (6), as a mixture of diastereoisomers in ca. 10:1 ratio, from which the major (S,Rp/R,Sp)-diastereoisomer is easily isolated by crystallisation. (S,Rp/R,Sp)-6 reacts with [Pd(LNC)(MeCN)2]ClO4 (LNC = 2-[(dimethylamino-κN)- methyl]phenyl-κC1) to give the cationic bis-chelate complex (S,Rp/R,Sp)-[Pd(LNC)(6-κ2O,P)]- ClO4 (9). The structures of (S,Rp/R,Sp)-6 and 9 have been determined by single-crystal X-ray diffraction. Hydrolysis of ester 6 to the corresponding carboxylic acid proved to be difficult, being complicated by racemisation at the chiral carbon atom and oxidation of the phosphanyl group.

Author(s):  
P. Vojtíšek ◽  
I. Císařová ◽  
J. Podlaha ◽  
Z. Žák ◽  
S. Böhm ◽  
...  

AbstractCrystal structures of the title compounds were determined by single crystal X-ray diffraction. Absolute configuration of the barium salt of (+)-(


1991 ◽  
Vol 46 (5) ◽  
pp. 566-572 ◽  
Author(s):  
Axel Gudat ◽  
Peter Höhn ◽  
Rüdiger Kniep ◽  
Albrecht Rabenau

The isotypic ternary compounds Ba3[MoN4] and Ba3[WN4] were prepared by reaction of the transition metals with barium (Ba3N2, resp.) under nitrogen. The crystal structures were determined by single crystal X-ray diffraction: Ba3[MoN4] (Ba3[WN4]): Pbca; Z = 8; a = 1083.9(3) pm (1091.8(3) pm), b = 1030.3(3) pm (1037.5(3) pm), c = 1202.9(3) pm (1209.2(4) pm). The structures contain isolated tetrahedral anions [MN4]6- (M = Mo, W) which are arranged in form of slightly distorted hexagonal layers and which are stacked along [010] with the sequence (···AB···). Two of the three Ba atoms are situated between, the third one is placed within the layers of [MN4]-groups. In this way the structures can be derived from the Na3As structure type.


1985 ◽  
Vol 38 (8) ◽  
pp. 1243 ◽  
Author(s):  
JC Dyason ◽  
LM Engelhardt ◽  
C Pakawatchai ◽  
PC Healy ◽  
AH White

The crystal structures of the title compounds have been determined by single-crystal X-ray diffraction methods at 295 K. Crystal data for (PPh3)2CuBr2Cu(PPh3) (1) show that the crystals are iso-morphous with the previously studied chloro analogue, being monoclinic, P21/c, a 19.390(8), b 9.912(5), c 26.979(9) Ǻ, β 112,33(3)°; R 0.043 for No 3444. Cu( trigonal )- P;Br respectively are 2.191(3); 2.409(2), 2.364(2) Ǻ. Cu(tetrahedral)- P;Br respectively are 2.241(3), 2.249(3); 2.550(2), 2.571(2) Ǻ. Crystals of 'step' [PPh3CuBr]4 (2) are isomorphous with the solvated bromo and unsolvated iodo analogues, being monoclinic, C2/c, a 25.687(10), b 16.084(7), c 17.815(9) Ǻ, β 110.92(3)°; R 0.072 for No 3055. Cu( trigonal )- P;Br respectively are 2.206(5); 2.371(3), 2.427(2) Ǻ. Cu(tetrahedral)- P;Br are 2.207(4); 2.446(2), 2.676(3), 2.515(3) Ǻ.


Author(s):  
William W. Brennessel ◽  
John E. Ellis

The reaction of the [K(18-crown-6)(thf)2]1+ (thf is tetrahydrofuran) salt of bis(anthracene)ferrate(−1), or [Fe(C14H10)2]−, with 2,6-dimethylphenyl isocyanide (CNXyl) in thf resulted in the formation of two new iron isocyanide complexes, namely, [(1,2,3,4-η)-anthracene]tris(2,6-dimethylphenyl isocyanide)iron, [Fe(C14H10)(C9H9N)3] or [Fe(1,2,3,4-η-C14H10)(CNXyl)3], and {5,6-bis(2,6-dimethylanilino)-3-(2,6-dimethylphenyl)-1,2,7-tris[(2,6-dimethylphenyl)imino]-3-azoniahept-3-ene-1,4,7-triido}tris(2,6-dimethylphenyl isocyanide)iron tetrahydrofuran disolvate, [Fe(C54H56N6)(C9H9N)3]·2C4H8O or [Fe(C54H56N6)(CNXyl)3]·2C4H8O, which were characterized by single-crystal X-ray diffraction. The former is likely an intermediate along the path to the known homoleptic [Fe(CNXyl)5], while the latter contains a tridentate ligand that is formed from the `coupling' of six CNXyl ligands. A third crystal structure from this reaction, (7-methylindol-1-ido-κN)(1,4,7,10,13,16-hexaoxacyclooctadecane-κ6 O)potassium, [K(C9H8N)(C12H24O6)] or [K(C9H8N)(18-crown-6)], contains a 7-methylindol-1-ide anion, in which one CNXyl ligand has shed a proton during its reductive cyclization.


2000 ◽  
Vol 55 (8) ◽  
pp. 677-684 ◽  
Author(s):  
Maciej Kubicki ◽  
Teresa Borowiak ◽  
Wiesław Z. Antkowiak

Abstract The tendency of forming mixed carboxyl-to-oxime hydrogen bonds was tested on the series of bornane derivatives: one with the acid function only (bornane-2-endo-carboxylic acid), one with the oxime function (2,2′-diethylthiobomane-3-oxime), and one with both oxime and carboxylic functions (bornane-2-oxime-3-endo-carboxylic acid). The crystal structures of these compounds were determined by means of X-ray diffraction. In bornane-2-endo-carboxylic acid and 2,2′-diethylthiobornane-3-oxime 'homogenic' hydrogen bonds were found, and these hydrogen bonds close eight-and six-membered rings, respectively. By contrast, in bornane-2-oxime-3-endo-carboxylic acid 'heterogenic' hydrogen bonds between carboxylic and oxime bonds were found. This carboxylic-oxime, or 'carboxyoxime' system is almost always present in compounds which have both oxime and carboxylic groups; therefore it can be regarded as an element of supramolecular structures (synthon). The presence of such synthons can break the tendency of carboxylic acids and oximes towards crystallizing in centrosymmetric structures.


2002 ◽  
Vol 57 (10) ◽  
pp. 1090-1100
Author(s):  
Franziska Emmerling ◽  
Caroline Röhr

AbstractThe title compounds were synthesized at a temperature of 700 °C via oxidation of elemental Bi with the hyperoxides AO2 or via reaction of the elemental alkali metals A with Bi2O3. Their crystal structures have been determined by single crystal x-ray diffraction. They are dominated by two possible surroundings of Bi by O, the ψ-trigonal-bipyramidal three (B) and the ψ-tetrahedral four (T) coordination. Cs6Bi4O9 (triclinic, spacegroup P1̄, a = 813.82(12), b = 991.60(14), c = 1213.83(18) pm, α = 103.658(2), β = 93.694(3), γ = 91.662(3)°, Z = 2) contains centrosymmetric chain segmentes [Bi8O18]12- with six three- (T) and two four-coordinated (B) Bi(III) centers. K9Bi5O13 (monoclinic, spacegroup P21/c, a = 1510.98(14), b = 567.59(5), c = 2685.6(2) pm, β = 111.190(2)°, Z = 4) is a mixed valence compound with isolated [BivO4]3- tetrahedra and chains [BiIII4O9]6- of two T and two B coordinated Bi. In the compounds A2Bi4O7 (A = Rb/Cs: monoclinic, C2/c, a = 2037.0(3) / 2130.6(12), b = 1285.5(2) / 1301.9(7), c = 1566.6(2) / 1605.6(9) pm, β = 94.783(3) / 95.725(9)°, Z = 8) ribbons [Bi4O6O2/2]2- are formed, which are condensed to form a three-dimensional framework.


1998 ◽  
Vol 51 (9) ◽  
pp. 867 ◽  
Author(s):  
Daniel E. Lynch ◽  
Lisa C. Thomas ◽  
Graham Smith ◽  
Karl A. Byriel ◽  
Colin H. L. Kennard

The crystal structure of the 1 : 1 adduct of N-methylaniline with 5-nitrofuran-2-carboxylic acid has been determined by single-crystal X-ray diffraction. Crystals are monoclinic, space group P21/c with Z 4 in a cell of dimensions a 8·467(5), b 6·106(2), c 23·95(1) Å, β 94·48(3)°. The molecules associate in a tetrameric, proton-transfer formation which has potential as a new supramolecular synthon.


1980 ◽  
Vol 33 (2) ◽  
pp. 313 ◽  
Author(s):  
PR Jefferies ◽  
BW Skelton ◽  
B Walter ◽  
AH White

Following the suggestion made earlier, on the basis of solution spectroscopy, that a number of eriostyl/nitrobenzoate compounds form charge-transfer self-complexes, a number of these have been investigated structurally by single-crystal X-ray diffraction methods in order to ascertain the presence or otherwise of such interactions in the solid state. The substances thus studied were eriostyl 3,5-dinitrobenzoate (1), eriostyl p-nitrobenzoate (2), tetrahydroeriostyl 3,5-dinitrobenzoate (3), and eriostemyl 3,5-dinitrobenzoate (4);* structure determinations in all cases, although displaying the presence of strong charge-transfer interactions from the two moieties of each molecule, show that the interactions in the solid state are intermolecular in nature.


1987 ◽  
Vol 42 (12) ◽  
pp. 1493-1499 ◽  
Author(s):  
Siegfried Pohl ◽  
Wolfgang Saak ◽  
Detlev Haase

AbstractThe compounds (Pn4P)4Sb8I28 (1) and (Ph4P)Sb3I10 (2) were prepared by the reaction of SbI3 and Ph4PI in acetonitrile (molar ratios 2:1 and 3:1 respectively). The structures of 1 and 2 were determined from single crystal X-ray diffraction data.1 crystallizes in the triclinic space group P1̄ with a - 1321.7(5). b = 1346.7(5), c = 2201.8(8) pm, α = 104.18(2). β = 99.92(2), γ = 100.33(2)°; 2: monoclinic, C2/c, a = 2371.1(2), b = 745.0(1), c = 2495.1(2) pm, β = 100.75(1)°.Whereas 1 exhibits isolated Sb8I284- ions, the anions of 2 are built up of polymeric chains [Sb3I10- ]∞. In both compounds the distorted Sbl6 octahedra are linked by common edges. The Sb-I distances are in the range between 277.4 and 354.8 pm (1) and between 277.4 and 342.4 pm (2). The observed structures do not only depend on stoichiometry, the nature of the counter cations, and the possibility of oligomerisation but also on the wide variety of the Sb-I bond strengths and the different bridges formed by iodine.The lone pair of Sb(III) seems to be predominantly 5 s2.


2000 ◽  
Vol 53 (10) ◽  
pp. 845 ◽  
Author(s):  
Margaret A. Brimble ◽  
Fares A. Fares ◽  
Peter Turner

A new method has been established for the preparation of C 2-oxidized 5,5-spiroacetals, which are key intermediates for the synthesis of the bis-spiroacetal moiety of the spirolides. A bridged orthoester was used as a masked carboxylic acid in the preparation of these bicyclic oxaspirolactones. The synthesis of chiral lactone (12), a building block for the synthesis of the spirolides, is also reported. The two chiral centres in lactone (12) were assembled by addition of a chiral crotyl borane to an aldehyde. The structure of lactone (12) was determined by single-crystal X-ray diffraction; orthorhombic space group P212121 (No. 19), a 12.437(2), b 23.881(4), c 7.545(1) Å, V 2240.9(5) Å3, R(F) 0.0460, and Rw(F) 0.0458.


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