Band 55, Heft 3-4

Reaction of OsCl 3 , with pentamethylcyclopentadiene in ethanol in air yields the ionic osmium( IV) compound [Cp* 2 OsCl] 2 [OsCl 6 ] which has been identified structurally and by vibrational spectroscopy. Under comparable conditions the RuCl 3 homologue yields the ruthenium( III) compound [Cp*RuCl 2 ] 2 , illustrating the more facile oxidation of the 5d element to the tetravalent state

Red-brown crystals of a new bis(thiomolybdate) complex [Me 4 N] 3 [(MoOS 3 ) 2 Ag] were formed at room temperature through the reaction of a solution of [Me 4 N] 2 [MoOS 3 ] in MeCN with solid AgCN. They are monoclinic, space group P2 1 /c with unit cell parameters a = 16.662(9), b = 9.464(3), c = 17.890(8) A, /3 = 101.87(2)°, Z = 4. The crystal structure was determined from single crystal diffractometer data (MoKα-radiation) and refined to R = 0.044 (3614 reflections, 236 variable parameters). The structure is characterized by trinuclear complex anions, [(MoOS 3 ) 2 Ag] 3- . According to Weissenberg investigations the homologous tungsten compound is isostructural. The infrared spectrum of the molybdenum complex (KBr powder) shows absorption bands at 884 (vs) and 871 (w) cm-1 (terminal v(Mo-0)), 483 (vs) cm -1 (terminal v(Mo-S)), 451 (vs), and 435 (w) cm -1 (bridging v(Mo-S)). The tungsten complex showed bands at 901 (vs) cm -1 (terminal v(W-O)), 478 (vs) cm -1 (terminal v(W-S)), and 435 (vs) cm -1 (bridging v(W-S)). The anionic mass spectra shows molecular ion peaks at m/z 524 and 700 for [(MoOS 3 ) 2 Ag] - and [(WOS 3 ) 2 Ag] - , respectively, as well as peaks for other fragments.

Metallic radii r m are correlated with the ionic radii r i by linear relationships. For groups 1 up to 7 as well as for AI, Ga, In, Tl, Sn, and Pb the ionic radii refer to the maximum valences (oxidation states) as known from compounds according to r m ≈ 1.16 • (r i + 0.64) [Å], For groups 8 up to 12, r m ≈ 0.48 · (r i + 2.26) [Å] with valences W = 14 -G (G = group number). These valences are considered regular (W r ). For groups 1 up to 12, they obey the equation W r = 7 -[G -71]. According to this equation all outer s electrons and the unpaired d electrons should be involved in chemical bonding, i.e. in the cohesion of the element in the solid state. From the melting temperatures and the atomic volumes it is concluded, however, that only 19 out of the 30 d-block elements have regular valences, namely the elements of groups 3, 5, 6, 10, 11 as well as Os, Ir, Zn, Cd, and possibly Ru. All of the non-regular valences are lower than the regular ones. Four of them are integers: Mn 3; Fe, Co 4; Re 6.

The first single crystal X-ray investigations of 3,4-lutidine complexes with mixed silicon tetrahalides were carried out

Bridged N-thiocarbamoyl substituted bis-benzamidines (C 2 H 5 ) 2 N-C(S)-N=C(Ph)-NH-R-NH-C(Ph)=N-C(S)-N(C 2 H 5 ) 2 with different moieties R (H 2 L 1 : R = diphenylmethane-2,2'-diyl, H 2 L 2 : R = diphenylmethane-3,3'-diyl, and H 2 L 3 : R = diphenylmethane-4,4'-diyl) were synthe­sized by the reaction of N-(thiocarbamoyl)benzimidoyl chlorides with diamines. These quadri­ dentate ligands form neutral mononuclear (CuL 1 ), dinuclear (Cu 2 L 3 2 ) and trinuclear (Cu 3 L 2 3 ) copper(II) chelates in dependence of the different bridging unit in the ligands. The compounds were characterized by NMR, IR, EPR and XPS spectroscopy and FAB mass spectrometry. The molecular structures of the ligand H 2 L 3 and the complex CuL 1 have been determined by X-ray methods.

Lanthanide, Carbacylamidophosphate The coordination compounds of the general formula Ln(NO 3 ) 3 (HL) 2 (H 2 O) 2 H 2 O , where Ln = La, Ce -Nd, Sm -Dy, HL = CCl 3 C(O)NHP(O)[N(CH 2 CH 2 ) 2 O] 2 , dimorpholido-N-tri-chloroacetylphosphorylamide, have been synthesized. The complexes were studied by IR, 1 H and 31 P NMR and UV-VIS absorption spectroscopies. X-ray diffraction analyses indicate that all synthesized compounds are isostructural. The crystal structure of Nd(NO 3 ) 3 (HL) 2 (H 2 O) 2 H 2 O was solved (monoclinic, a = 11.0467(3), b = 15.9080(5), c = 24.1921(7) Å, β = 96.4080(10)°, space group P2 1 /n, V = 4224.7(2) Å 3 , Z = 4, R = 0.049, wR = 0.0915). The complex has a molecular structure. The monodentate neutral phosphorictriamide ligands are coordinated to the metal atom via the phosphoryl oxygen atom. The coordination polyhedron of Nd is a sphenocorona; C.N. = 10(60[NO 3 - ], 20[HL], 20[H 2 O]). It was shown that these compounds in methanol solution are 1:1 electrolytes, and in acetone solution weak electrolytes. According to NMR data in acetone solution the complexes of the lanthanides with the ligand {HL} have axial symmetry.

Cs[(CF 3 ) 3 BNH 2 ] reacts with CF 3 NO to form cesium trans-trifluoromethyldiazenido-tris(trifluoromethyl) borate Cs[(CF 3 ) 3 BN=NCF 3 ] (2), the structure of which has been investigated by single-crystal X-ray diffraction. The diazene nature of the anion is confirmed by the length of the N=N bond, 1.231(6) Å, and the size of the N-N-B angle, 115.5(4)° - the B-N bond length being 1.559(7) A. Compound 2 is hitherto the first diazenidoborate which has been fully characterized

The crystal structure of Bi 3 Se 4 Br has been determined. With respect to its (Bi,Se) substructure it is related to orthorhombic Bi 2 Se 3 and to Bi 19 S 27 Br 3

Thermodynamic data of the complexation of cobalt(II), nickel(II), and copper(II) ions with pyridine (py), 2-methylpyridine (2Me-py), 3-methylpyridine (3Me-py), and 4-methylpyridine (4Me-py) have been determined by calorimetry and spectrophotometry in acetonitrile (MeCN) containing 0.1 mol dm -3 (C 2 H 5 ) 4 NClO 4 as a constant ionic medium at 25 °C. The calorimetric and spectrophotometric data for py, 3Me-py, and 4Me-py revealed the formation of [ML] 2+ , [ML 2 ] 2+ , [ML 3 ] 2+ , and [ML 4 ] 2+ (M = Co 2+ , Ni 2+ , Cu 2+ ; L = py, SMe-py, 4Me-py). For 2Me-py, on the other hand, the formation of only one complex, [M(2Me-py)] 2+ (M = Co 2+ , Ni 2+ ), was detected. The stepwise thermodynamic quantities and the individual electronic spectra of the complexes suggest that all of these have a six-coordinate octahedral structure. The stability of the [M(2Me-py)] 2+ (M = Co 2+ , Ni 2+ ) complexes is much lower than that of the corresponding py, 3Me-py, and 4Me-py complexes. The difference in the stability of the 2Me-py complexes is mainly due to their unfavorable entropy changes because the differences of enthalpies for all the complexes are not so significant. The free energies for the formation of the mono complexes follow the order Mn(II) > Co(II) > Ni(II) > Cu(II) < Zn(II) for the py, 3Me-py, and 4Me-py systems. The ΔH° 1 values vary in the same order and the ΔS° 1 values are similar. Hence, the stability difference of the mono complexes originates from the enthalpic term

The cationic thorium(IV) complexes [Th{Ph 2 P(O)CH 2 CH 2 P(O)Ph 2 } 2 (NO 3 ) 3 ]NO 3 and [Th{Ph 2 P(O)NP(O)Ph 2 } 3 (dmso) 2 ]NO 3 have been synthesized by reactions of Th(NO 3 ) 4 · 5H 2 O with bis(diphenylphosphino)ethane dioxide, Ph 2 P(O)CH 2 CH 2 P(O)Ph 2 (L 1 ), or ammonium bis(diphenylphosphoryl)amide, (NH 4 )[Ph 2 P(O)NP(O)Ph 2 ] (NH 4 L 2 ), and subsequent recrystallization from dimethyl sulfoxide. The products have been studied spectroscopically and by X-ray crystallography. The thorium atom is ten-co-ordinate in the [Th(L 1 ) 2 (NO 3 ) 3 ] + cation with a coordination sphere which does not match one of the idealized polyhedra for ten-coordination. Th-O bonds have been found in the range between 2.342(3) (phosphine oxide) and 2.599(4) A (nitrate). An eight-coordinate thorium atom is found in the [Th(L 2 ) 3 (dmso) 2 ] + cation. The almost ideal square-antiprismatic environment of the metal is occupied by oxygen atoms with Th-0 bond lengths between 2.363(6) and 2.392(11) Å

A new synthetic approach for the low- and mixed-valence double titanium phosphates starting with titanium nitride, TiN, and based on the controlled oxidation of a low-valent metal in the phosphate melt is presented. The reaction of the system M I 2 O - P 2 O 5 - TiN (M I = Na, K) in air (800-1050 °C) leads to loss of nitrogen, N 2 , and results in the formation of a number of double phosphates: KTiP 2 O 7 , K 2 TiniTiIV(PO 4 ) 3 , KTiOPO 4 , NaTiP 2 O 7 , NaTi 2 (PO 4 ) 3 and a new mixed-valent diphosphate, NaTi III Ti IV (P 2 O 7 ) 2 . The mixed-valent species K 2 Ti III Ti IV (PO 4 ) 3 and NaTi III Ti IV (P 2 O 7 ) 2 were characterized by single crystal X-ray diffraction. The described synthetic procedure is proposed as a simple and convenient method for the preparation of lowand mixed-valent phosphate materials

In a study aim ed at the „deconstruction“ of the supramolecular aggregate 3(18C6) · 2HN( SO 2 Me) 2 (1,18C6 = 18-crown-6), which is known to display a ladder structure with two isotactic [18C6 - Me SO 2 N(H)SO 2 Me···)∞ polymers forming the uprights and symmetrically N - H···O bonded 18C6 rings providing the rungs, the following crystalline complexes were isolated and (except for 2b) characterized by low-temperature X-ray diffraction: 18C6-ClN (SO 2 Me) 2 (2a, triclinic, space group P1̅, Z = 2), 18C6-PhN (SO 2 Me) 2 (2b), 18C6 -MeN(SO 2 Me) 2 (3, monoclinic, P2 1 /c, Z = 8), Bz18C6-HN(SO 2 Me) 2 (4, Bz18C6 = benzo-18-crown-6, monoclinic, P2 1 /n, Z = 4), 18C6-2 MeN (SO 2 Me) 2 (5, triclinic, P1̅, Z = 1), 18C6-Me 2 SO- HN( SO 2 Me) (SO 2 Ph) (13, triclinic, P1̅, Z = 2), and 18C6-H 2 OMe 2 SO·2HN(SO 2 Me) 2 (14, triclinic, P1̅, Z = 2). Each of the one-dimensional polymers 2a (syndiotactic), 3 (disyndiotactic) and 4 (isotactic) mimics a single upright of 1; in contrast to 1 and 2a, where the intra-catemer connectivity solely relies on S - Me ··· crow n and crown ··· O = S hydrogen bonds, this bonding system is reinforced in 3 by N -Me ··· crown and in 4 by N - H ··· crown hydrogen bonds. Complex 5 is monomeric and matches a fragment formally extruded from the catemer 3; moreover, 3 and 5 represent a rare case of two structurally characterized 18C6 complexes containing the same uncharged guest species in distinct molecular ratios. The surprising structure of the quaternary adduct 14 exhibits an [18C6 ··· MeSO 2 N(H)SO 2 Me ··· ]∞ chain, which can be regarded both as an isolated, though unmodified upright from the ladder 1 and, being syndiotactic, as a stereochemical analogue of 2a; the potentially rung-forming *NH functions in the chain are blocked by hydrogenbonded side chains of the type * N - H ··· water ··· sulfoxide ··· H - N (SO 2 Me) 2 . The ternary complex 13 consists of chains [18C6 ··· Me 2 SO ··· H - N (SO 2 Ph)SO 2 Me···]∞ and is not closely related to the other structures

Ozonolysis of 3,6-anhydro-4-0-(p-toluenesulphonyl)-D-glucal (9), obtained in four steps from D-glucose, provided the target compound 11. The structure and configurations of 9 and 11 have been determined by spectral studies and X-ray crystallography. Similar strategy with D-galactose provided the corresponding derivatives 10 and 12, respectively

Utility of 3-aminocinnamonitrile (1) in the synthesis of new 1,4-dihydropyridine, pyrazolo- [1,5-a]pyrimidine, aminothiophene and pyridine derivatives is reported

Extractions of ginsenosides from ginseng roots with liquid ammonia, methanol/water (60:40; v/v) or water were carried out. The extracts have been analyzed qualitatively and quantitatively to valuate yield and selectivity of extractions of ginsenosides. Water supplied the lowest yield. The yields of extracts with liquid ammonia were higher than those with m ethanol-water (60%). Yields of the ginsenosides Rb 1 , Rb 2 , Rc and Rd by extracting with liquid ammonia are about twice as much as those of the extraction with methanol-water (60%). It was proved by HPLC that malonyl-ginsenosides m -Rb 1 m-Rb 2 , m-Rc and m-Rd were converted to the corresponding neutral ginsenosides by extraction with liquid ammonia. Because of high yields of extracts and simultaneous increase of the contents of Rb 1 , Rb 2 , Rc and Rd the extraction with liquid ammonia is obviously superior to the other extraction methods. Furtherm ore, ginsenosides from ginseng roots were extracted by alkaline methanol-water (60%) solutions. Alternatively, the extracts of the methanol-water (60%) extraction were treated with sodium hydroxide solution. Both methods convert also the malonyl-ginsenosides to neutral ginsenosides

A mixture of the title compound-(6′) stearate, margarate, palmitate, linolate, and linole- nate (2a-e) was isolated from shredded dried leaves and twigs of Flacourtia indica. The margarate was observed for the first time. 0.5% solutions of the triacetate mixture (1a-e) in methanol or ethanol give “solid" gels stable for months. From these the unchanged triacetates 1a-e can be recovered indicating that this low-molecular material is responsible for the formation of the gel.

N-protonation of 5,10,15,20-tetraalkylporphyrins with n-butyl, isobutyl, isopropyl, 1-ethyl-propyl or tert-butyl substituents yields the respective 22,24-dihydroporphyrins (22H + ,24H + -porphyrindiium salts) that exhibit highly nonplanar conformations. Depending on the steric demand of the meso substituents, the free base porphyrins have planar to moderately ruffled macrocycles (primary or secondary alkyl residues) or are severely ruffled (tertiary alkyl resi­dues). X-ray crystallographic studies show that protonation of porphyrins with n-Bu (2), i-Pr (3) or EtPr (4) substituents leads to steric congestion of the core resulting in symmetric, saddle distorted macrocycles as evidenced by average displacements of the Cb positions from the mean plane ranging from 0.79 to 1.01 Å. The structures observed for these porphyrin diacids are very similar in distortion mode and degree of nonplanarity to 5,10,15,20-tetraaryl-22H + ,24H + -porphyrindiium salts and to 2,3,7,8,12,13,17,18-octaalkyl-5,10,15,20-tetraaryl-porphyrins. In contrast, protonation of the highly ruffled 5,10,15,20-tetrakis(teA-r-butyl)porph-yrin results in a switch of the conformational distortion mode. The dication 6 shows both saddle distortion (C b displacements -1.3 Å) and ruffling of the macrocycle (C m displacements of approx. 0.48 Å). Thus, the need to accomodate four N-H units in the porphyrin core with its associated out-of-plane tilting of the pyrrole rings and the steric strain induced at the meso carbon atoms results in a highly nonplanar porphyrin with mixed distortion modes.

The vinamidinium chloride C 7 H 15 N 2 Cl (5) is obtained from the corresponding vinamidine C 7 H 14 N 2 (4) and HCl; the X-ray structure reveals a polymeric nature consisting of w-shaped cations connected with the chloride ions by hydrogen bonds