Volume 54, Issue 11

Lithium ozonide has been synthezised starting from cesium ozonide via cation exchange in liquid ammonia and crystallizes at -78°C as an ammoniate, LiO 3 · 5NH 3 . The coarse, ruby red crystals decompose above the boiling temperature of ammonia and are extremely sensitive to moisture. The crystal structure of L iO 3 · 5NH 3 (P c2 1 n; a = 1231.9(5), b = 637.4(2), c = 1104.8(4) pm; Z = 4; R 1 = 4.57%; 1318 independent reflections) consists of lithium tetramine complexes, ozonide anions and non coordinating ammonia molecules. With respect to the arrangement of the complex cations and of the anions there is similarity to the WC type of structure. The central oxygen atom of the ozonide anion is disordered.

The first examples of carbene-cadmium complexes are reported from the reactions of a variety of imidazol-2-ylidenes or imidazolin-2-ylidenes with dimethylcadmium. Four new carbene complexes are characterized by NMR spectroscopy ( 1 H , 13 C and 113 Cd). The cadmium centers are strongly shifted downfield (100 -150 ppm) by interaction with the carbenes. X-ray structures are reported for three carbene-cadmium 1:1 adducts. The cadmium centers exhibit distorted trigonal-planar geometries in which the carbene ligands have an average 18.2 pm longer bond distance to cadmium compared to the methyl groups. The planes of cadmium coordination are twisted with respect to the plane of the imidazole ring. The more basic imidazolin-2-ylidene is shown to displace imidazol-2-ylidenes from the cadmium center.

The bis(N,N′-morpholido)-[(N″-morpholido)-carboxamido] phosphate: O(CH 2 CH 2 )NC(O )-N(H)P(O)[N(CH 2 CH 2 )O] 2 [HL], has been prepared and characterized by means of IR, 31 P and 1 H NMR spectroscopy and X-ray diffraction (triclinic, a = 9.282(2), b = 9.308(2), c = 21.341(4) Å, α = 80.79(3)°, β = 80.92(3)° γ = 66.92(3)°, V = 1665.1(6) Å 3 , space group P1̄̄, Z = 4 and R = 0.0423, wR2 = 0.1303 for 6774 unique reflections used). The unit cell consists of two independent molecules connected by hydrogen bonds N-H...O=P into non-symmetric dimers. The compound behaves as a HL molecule with a protonation constant corresponding to the -C(O)N(H)P(O)- group of pK = 8.65 as determined by potentiometric studies.

The chiral orthometallated palladium complex (S)-[Pd{C 6 H 4 (CH(CH 3 )N(CH 3 ) 2 )-C,N}Cl] 2 (1) can be used as a reagent for the determination of the enantiomeric ratio of α-amino acids. By reaction of 1 with mixtures of several D- and L-α-amino carboxylates diastereoisomers of the α-amino acidato complexes 2a - g are obtained. 1 NMR determination of the ratio of the diastereoisomers provides the D/L-ratio of the used D- and L-α-amino carboxylates and is therefore a simple method for the determination of the enantiomeric ratio of α-amino acids.

1,1,1,3,3,3-Hexaamino-1λ 5 ,3λ 5 -diphosphazenium bromide [(NH 2 ) 3 PNP(NH 2 ) 3 ]Br, nitrate [(NH 2 ) 3 PNP(NH 2 ) 3 ][NO 3 ], and toluene-4-sulfonate [(NH 2 ) 3 PNP(NH 2 ) 3 ][CH 3 C 6 H 4 SO 3 ] have been prepared by anion exchange in aqueous solution. Single crystals were obtained from acetonitrile solutions in a temperature gradient between 60 °C and room temperature. The crystal structures were determined by single crystal X-ray methods at room temperature. ([(NH 2 ) 3 PNP(NH 2 ) 3 ]Br: P1̄̄ , Z = 2, a = 596.2( 1 ),b = 744.5( 1), c = 1114.4( 1) pm, α = 108.78( 1), β = 104.18(1), γ = 90.64(1)°, R 1 = 0.048, wR2 = 0.104; [(NH 2 ) 3 PNP(NH 2 ) 3 ][NO 3 ]: P1̄̄, Z = 2, a = 550.9( 1), b = 796.3( 1), c = 1115.7( 1) pm, α = 94.45( 1), β= 99.55( 1), γ = 101,53( 1)°, R1 = 0.033, wR2 = 0.095; [(NH 2 ) 3 PNP(NH 2 ) 3 ][CH 3 C 6 H 4 SO 3 ]: P2 1 /c, Z = 4, a = 804.1(1), b = 596.1(1), c = 3218.7(3) pm, β = 94.59(1)°, R1 = 0.052, wR2 = 0.136). In the solid the three salts consist of discrete [(NH 2 ) 3 PNP(NH 2 ) 3 ] + cations and their corresponding anions. The PN 4 tetrahedra in [(NH 2 ) 3 PNP(NH 2 ) 3 ]Br are staggered, while in [(NH 2 ) 3 PNP(NH 2 ) 3 ][NO 3 ] the eclipsed conformation is preferred. The PN 4 tetrahedra of [(NH 2 ) 3 PNP(NH 2 ) 3 ][CH 3 C 6 H 4 SO 3 ] show gauche conformation.

Reaction of 2,5,5-trimethyl-Δ 1 -pyrrolidine-N-oxide with methyl lithium yields 2,2′-bis(1-hydroxy- 2,2,5-trimethyl-pyrrolidinyl)methane which is reduced by Raney nickel/hydrogen to the corresponding amine. Both molecules are present in the meso-configuration in the solid state. While the hydroxylamine derivative shows intermolecular O-H···O bridge bonding no intermolecular N···H-N interaction is observed for the amine.

The synthesis of RbHCN 2 was carried out by reaction of cyanamide with rubidium amide in liquid ammonia. The crystal structure has been determinedo by x-ray powder methods (orthorhombic, P2 1 ,2 1 ,2 1 , a = 7.299(1), b = 9.435(1), c = 9.420(1) Å; Z = 8). The anion is slightly bent (174°) and exhibits two different bond lengths (C-N: 1.17, HN-C: 1.31 Å).

The interaction of NdCl 3 with lithium metal in THF in the presence of naphthalene produces a mixture of naphthalene complexes of di- and trivalent neodymium chloride of an aggregate composition [NdCl 2 (THF) 2 LiCl] n C 10 H 8 (n = 4- 7). By the reaction of these compounds with 2,4,6-t-Bu 3 C 6 H 2 OH in THF the complex [{NdCl 2 (2,4,6-t-Bu 3 C 6 H 2 O)(μ-Cl)(THF)}Li(THF) 2 ] 2 has been obtained in 70% yield and its X-ray crystal structure determined.

Synthetic tinsleyite K[Al 2 (PO 4 ) 2 (OH)(H 2 O)]·H 2 O has been obtained by the reaction of gibbsite with a potassium-phosphate solution of pH = 7 at 423 K within five days. A single crystal X-ray structure analysis has shown that synthetic tinsleyite is isotypic with the mineral leucophosphite K[Fe 2 (PO 4 ) 2 (OH)(H 2 O )]·H 2 O. Crystal data: monoclinic space group P2 1 /n,a = 949.9(2), b = 950.3(2), c = 953,5(2) pm, β = 103,26(3)°, Z = 4. The structure of tinsleyite consists of tetranuclear A I 4 O 2 units formed by a central pair of edge sharing AlO 6 octahedra, to which two additional AlO 6 octahedra are attached sharing corners. These units are crosslinked by phosphate ions to a three dimensional framework structure with tunnels along [010], occupied by potassium cations. While one type of water molecules is attached to Al, a second type is fixed in the structure by hydrogen bonds only. As a consequence two steps for thermal loss of water at 341 K and 471 K are observed.

N-Trimethylsilylaminotitanium trichlorides, Me 3 Si(R)N-TiCl 3 [R = t Bu (2a), SiMe 3 (2b), 9-borabicyclo[3.3.1 ]nonyl (9-BBN) (2c)] react with the corresponding plumbylenes 1a - c or with the lithium amides LiN(R)SiMe 3 to give the bis(amino)titanium dichlorides 3a - c, and 4 - 6. The titanium dichlorides 4-6 are the first examples, in which the titanium atom bears two different amino groups. The compounds were characterised by a consistent set of 1 H, 13 C, 14/15 N and 29 Si NMR data.

N,N′-Bis(trimethylsilyl)benzamidinato complexes of vanadium(V), niobium(V) and tantalum( V) have been prepared starting from t BuN=MCl 3 · n py and t BuN=MCpCl 2 , respectively: t BuN=V[PhC(NSiMe 3 ) 2 ] n Cl 3 -n (n = 1, 2); t BuN=M[RC(NSiMe 3 ) 2 ]Cl · py [M = Nb. Ta; R = C 6 H 5 , C 6 H 4 (4-CF 3 )]; t BuN=MCp[RC(NSiMe 3 ) 2 ]Cl [M = V. Nb, Ta; R = C 6 H 5 , C 6 H 4 - (4-CF 3 )]; t BuN=VCp[PhC(NSiMe 3 ) 2 ](O t Bu). The syntheses of silylated tert-butylamido complexes tBuN=M[NtBu-SiMe 2 -NH t Bu]Cl 2 · py (M = Nb, Ta), t BuN=V[N t Bu-SiMe 2 -O t Bu]Cl 2 and t BuN=M[N t Bu-SiMe 2 -O t Bu]Cl 2 · py [M = Nb, Ta (20)] are also described. The compounds have been investigated by 1 H NMR data, 51 V NMR data, mass spectra. X-ray data diffraction analysis.

The preparation, crystal structures, optical absorption spectra, and photoluminescence spectra of the title compounds are reported. The compounds were prepared in single crystal form. [C 6 H 5 CH 2 NH 3 ] 2 PbI 4 consists of anionic perovskite sheets of corner-sharing Pbl 6 octahedra, which alternate with the C 6 H 5 CH 2 NH 3 + sheets. [ C 6 H 5 CH 2 CH 2 SC(NH 2 ) 2 ] 3 PbI 5 consists of zig-zag chains of anionic corner sharing PbI 6 octahedra separated by C 6 H 5 CH 2 CH 2 SC(NH 2 ) 2 cations. [C 10 H 7 CH 2 NH 3 ]Pbl 3 consists of twin chains of edge-sharing PbI 6 octahedra separated by C 10 H 7 CH 2 NH 3 cations. The compounds are thus low-dimensional systems. The excitonic spectra were observed in all cases, even at room temperature, and the possibility of organicinorganic excitonic interactions is discussed.

The thermodynamical data of solid aluminium lanthanum chloride LaAlCl 6 have been obtained by determination of the decomposition equilibria from total pressure measurements. The melting diagram was determined by DTA. The chemical transport of LaCl 3 with AlCl 3 is suggesting the existence of the gaseous complex LaAl 3 Cl 12 . The data are: ΔH(LaAlCl 6 f,298 ) =-427,1 ±2,5 kcal/mol, S°(LaAlCl 6,f,298 ) = 61 ±2,5 cal/K-mol, Δ(LaAl 3 Cl 12,g ,298 ) =-712 ± 7 kcal/mol, S°(LaAl 3 Cl 12,g,298 ) = 205 ± 3 cal/K-mol.

Anhydrous indium trichloride reacts with [2-(Ph 2 P)C 6 H 4 ] 2 PPh (TP) in the molar ratio 2:1 to give an ionic complex [(TP)InCl 2 ] + InCL 4 - in almost quantitative yield. The structure of the product has been determined by a single crystal X-ray diffraction study. In the cation the TP molecule acts only as a bidentate ligand via its two terminal phosphorus atoms [In-P1 2.5956(8), In-P2 2.5799(7) Å], Although the central phosphorus atom is also rather close to the metal atom [2.8259(8) Å], the In-P3 interaction is inefficient because of an adverse orientation of the lone pair of electrons at P3 owing to the steric inflexibility of the ligand. Accordingly, the 31 P NMR spectra of the compound in CD 2 CI 2 show large contact shifts and quadrupole broadening only for the signals of the two terminal phosphorus atoms, whereas the lines of the central phosphorus atom are less shifted and well resolved (AB 2 spin system at -60°C).

In order to examine packing preferences and hydrogen bond patterns in secondary ammonium salts, low-temperature X-ray analyses were conducted for six compounds of general formula R 2 NH 2 + MeSO 2 ) 2 N - , where R 2 NH 2 + = Me 2 NH 2 + (1, triclinic, space group P1̄̄), MeEtNH 2 + ,(2, monoclinic, P2 1 /c), Et 2 NH 2 + (3. triclinic, P1), pyrrolidinium (4, triclinic, P1), piperidinium (5, monoclinic, C2/c) or morpholinium (6, monoclinic, P2 1/ c). Throughout the series, the constant anion retains a rigid conformation approximating to C 2 symmetry and thus provides a geometrically reliable set of five potential hydrogen bond acceptors. Nevertheless, the six compounds exhibit a variety of unpredictable packing patterns, showing that, in unfavourable cases, the steric demands of molecular fragments not involved in hydrogen bonding can substantially alter the structure of a family of ionic crystals. In the present structures, the NH 2 + donor groups form hydrogen bonds N + -H···N - /O to two (3-6) or three (1,2) adjacent anions. The occurrence of various two-, three- and four-centre hydrogen bonds leads to six different patterns, resulting in cation-anion layers (1, 2), discrete formula unit dimers (3, 4) or cation-anion chains (5, 6); in the morpholinium salt 6, these chains are associated into layers by a weak N + - H ··· O(cation) interaction. In each of the crystal packings, short C-H···O contacts with H···O ≤ 270 pm and C-H ···O ≥ 130° are observed.

In order to study hydrogen bonding patterns in primary ammonium salts and the hydrogen bond acceptor potential of the dimesylamide anion, low-temperature X-ray structures have been determined for the 1:1 salts RNH 3 + (MeSO 2 ) 2 N - , where R = Et (1, monoclinic, space group P2 1/ n, two independent formula units A and B) or 1-adamantyl (2, monoclinic, P2 1/C ) and for the 1:2 salt [H 3 NCH 2 CH 2 NH 3 ] 2+ ·2 (MeSO 2 ) 2 N - (3, monoclinic, P2 1/ n, cation crystallographically centrosymmetric). The NH 3 + donor groups form two-centre or three-centre hydrogen bonds to four (B) or three (A, 2, 3) adjacent anions, giving rise to fundamentally different networks. The crystal packing of 1 displays a three-dimensional system of eight independent H bonds and may be viewed as a commensurate ionic self-clathrate, in which finite (A) 2 cyclodimers are inserted as guest entities into parallel tunnels between infinite (B)∞ tapes. In contrast, owing to the steric demands of the 1-adamantyl group, compound 2 merely exhibits a twodimensional pattern constructed from four independent H bonds and leading to cation-anion sheets. In the packing of 3, two crystallographically independent H bonds generate a tape substructure of cations and anions in the ratio 1:2; these tapes are cross-linked into a three-dimensional network via a third independent H bond. In each of the structures, short C -H ··· A contacts (A = N - and/or O) with H ··· A ≤ 260 pm and C - H ··· A ≥ 130° are observed.

Syntheses and low-temperature X-ray structures are reported for three ionic solids of general formula BH + (MeSO 2 ) 2 N - , where BH + is 3,4,6,7,8,9-hexahydro-2H-pyrimido[1,2-a]pyrimidinium (1, monoclinic, space group P2 1 /c), N,N′-diphenylformamidinium (2, monoclinic, P2 1/ c), or 2-phenylaminopyridinium (3, triclinic, P1̄̄, two independent formula units). As a common feature, the onium cations in question exhibit a difunctional hydrogen-bond donor sequence H -N -C (sp 2 ) - N - H geometrically complementary to an O - S - N fragment of the anion. Consequently, the three crystal packings consist of discrete cation-anion pairs (formula units) assembled by an N -H ··· N and an N - H O hydrogen bond. In both independent ion pairs of 3, the N -H ··· N bond originates from the pyridinium centre and the N - H - O bond from the amino group. The eight-membered ring [graph set N 2 = R 2 2 (8), antidromic] that results in all these prototypical structures has potential as a new and robust supramolecular synthon. In each case, short C - H ··· O contacts with H ··· O ≤ 260 pm and C - H ··· O ≥ 140° are present; in 2, two C ar - H ··· O hydrogen bonds are assisted by a C(formyl)- H ··· O contact and a π - π interaction to create a centrosymmetric formula unit dimer.

The reactivity of diferrocenylamine has been investigated aiming at the preparation of novel diferrocenylamino compounds, including nitrenium salts, amino radicals, transition metal amides, carbamato ligands, and others. However, diferrocenylamine is unexpectedly difficult to derivatize; only simple metalation by butyl lithium, alkylation by iodomethane, and chloroformylation by phosgene were possible. X-ray crystal structures are reported for the starting diferrocenylamine, and for the derivatives diferrocenylmethylamine and N,N diferrocenylcarbamoylchloride.

The partially oxidized cyclotriphosphane (PB u t ) 3 O (1,2,3-tri-tert-butyl-1-oxocyclotriphosphane) (1) has been obtained by [2 + 1] cyclocondensation of K (Bu t )P-P(Bu t )K with Bu t P(O)Cl 2 in toluene at -78 °C. The cyclophosphanes (PBu t ) 4 and (PBu t ) 3 as well as small amounts of the open-chain triphosphane [Bu t P(O)Cl] 2 P (O)Bu t are also formed. In contrast to the unoxidized compound (PBu t ) 3 , compound 1 is not stable at room temperature, but decomposes above -30 °C undergoing rearrangement into the cyclotetraphosphanes (PBu t ) 4 O (2), (PBu t ) 4 O 2 (3), and (PBu t ) 4 . The 31 P NMR parameters of 1 and 3 are reported and discussed.

A novel class of nucleoside analogues containing adenine, uracil, thymine and 5-fluorouracil as the heterocyclic moieties have been prepared from 2-phenylcyclopropane carboxylic acid. These compounds showed weak antitum or activity. The resolution of the racemates on an analytical and semipreparative scale was performed by HPLC using chiral stationary phases.

The synthesis and spectral properties (IR, MS, NMR) of a substituted 5-(2,3-dihydro-7- benzofuryl)pyrazolo[4,3-d]pyrimidin-7-one (2), an analog of Viagra® (1), are described. The generally applicable route involves interaction of 2,3-dihydro-7-benzofuranoyl chloride (3) with 4-amino-l-methyl-3-propyl-5-pyrazolecarboxamide (4), and the resulting bis-amide (5) is cyclized to the corresponding substituted pyrazolo[4,3-d]pyrimidin-7-one (6). Chlorosulfonylation of 6, followed by treatment with 1-methylpiperazine, furnished the title compound 2 (named Biagra). Preliminary experiments “associated with the erectile process” on rats lend evidence of greater potency of Biagra (2) as compared to Viagra® (1).

In the crystal structure of (dppmSe) 2 Au + N(SO 2 CH 3 ) 2- (dppm = Ph 2 PCH 2 PPh 2 ) chains are formed from non-conventional hydrogen bonds of the type C -H ···O . Within these chains two bifurcated hydrogen bond systems are present, each involving one methylene hydrogen (H···O 2.51, 2.65 Å) and one phenyl hydrogen (H···O 2.31, 2.35 Å) as donors.

1,1,3,3-Tetrakis(dimethylamino)-1λ 5 ,3λ 5 -diphosphete, (1), reacts with 2-cyano-pyridine to yield 6- pyridyl-1-aza-2λ 5 ,4A 5 -diphosphinine (3). 3 is characterized by its 1 H , 31 P, and 13 C NMR, mass, and IR spectra as well as the results of the X-ray structure analysis.