Volume 37, Issue 7

A complete analysis of the 31 P, 13 C and 1 H NMR spectra of tri-tert-butyl-cyclotriphosphane (1) was carried out and the resulting NMR parameters were correlated with the X-ray data of the molecule. It was found, that increasing P-P-C-bond angles correspond to a downfield shift and an increase of the absolute values of the negative 1 J(PP) and 1 J(PC) coupling constants. Generally, the chemical shifts of cyclotriphosphanes as well as of larger cyclic phosphanes depend on the endo- and exocyclic bond angles, the dihedral angle between the electron lone pairs of adjacent P-atoms, and the β-effect. On the basis of the X-ray and chemical shift data of 1, the bond angles of other cyclotriphosphanes can be deduced from their δ( 31 P) values. 1 crystallizes triclinically in the space group P1̄ with Z = 4 formula units. The X-ray analysis confirms the NMR-spectroscopically determined three-membered ring structure with the tert-butyl substituents on either side of the ring plane. Due to steric hindrance between the two tert-butyl groups in cis position, the corresponding P-P-C-bond angles show the largest values so far observed for organylcyclophosphanes.

X-ray analysis of [N(CH 3 ) 4 ] 6 S 2 V 2 W 16 O 62 furnishes evidence for the existence of a discrete heteropolysulfate ion. The compound crystallizes monoclinic, space group P2 1 /C with lattice parameters a = 13.361(5) Å, b = 25.378(1) Å, c = 28.847(5) and β = 91.37(3)°. Its anion has the configuration (Dawson structure) first observed in K 6 P 2 W 18 O 62 · 14 H 2 O. [N(CH 3 ) 4 ] 2 NaVW 5 O 19 · H 2 O, formed as a side product in the preparation of the hetero-polysulfate, crystallizes in the orthorhombic space group Pmnm with lattice constants a = 12.810(3) Å, b = 10.842 Å and c = 9.703(4) Å. Its anion belongs to the known hexa-metallate type M 6 O 19 z− . The sodium ion is pentacoordinate (trigonal bipyramidal). The water of crystallization belonging to its coordination sphere exhibits the extremely short Na-O distance of 2.19 Å. The Na + ··· H 2 O grouping appears to cause an IR as well as Raman active vibration band at 1290 cm -1 .

Diphenylbismuth carboxylates Ph 2 BiX (X = OAc = CH 3 COO, C 2 H 5 COO, C 3 H 7 COO, Me 2 CHCOO, Me 3 CCOO, CH 3 COCH 2 CH 2 COO, PhCOO; Me = CH 3 ; Ph = C 6 H 5 ) have been prepared from Ph 2 BiCl and NaX or from Ph 2 BiOC 2 H 5 and HX in anhydrous ethanol. PhoBiOAc and a compound of approximate composition PhBi(OAc) 2 have been obtained in small yields from acidolysis of Ph 3 Bi with HOAc (molar ratio 1:1 and 1:3, resp.) in acetone. A polymeric structure with bridging bidentate carboxylate groups is proposed for Ph 2 BiX compounds.

Potassium Sodium Oxide, Rubidium Sodium Oxide The compounds KNaO and RbNaO have been prepared and their structures determined by powder and single crystal data. Both compounds show the anti-PbFCl crystal structure type with two molecular units. KNaO: a = 400.2(1) pm, c = 621.4(2) pm, c/a= 1.553; RbNaO: a = 409.3(9) pm, c = 653.1(9) pm, c/a = 1.595. Abstract The compounds KNaO and RbNaO have been prepared and their structures determined by powder and single crystal data. Both compounds show the anti-PbFCl crystal structure type with two molecular units. KNaO: a = 400.2(1) pm, c = 621.4(2) pm, c/a= 1.553; RbNaO: a = 409.3(9) pm, c = 653.1(9) pm, c/a = 1.595.

Adenine (1) is formed in substantial amounts (about 1% yield) by heating ammonium cyanide absorbed in zeolithe X for several days at 120 °C. If both, ammonium cyanide and cyanic acid have been absorbed, 1 and guanine (2) are synthesized under the same conditions. These experiments provide the first demonstration of the possibility of a spontaneous synthesis of these essential constituents of nucleic acids and of important coenzymes in a silicate.

The crystal structure of (OC)AuCl has been determined and refined to R 0.037 (space group Cmcm, a = 407.1(1), b = 1042.2(4), c = 532.1(3) pm, Z =4). The structure consists of discrete, exactly linear molecules; all atoms lie on the special positions 0, y, 1/4. The bond lengths involving the light atoms are affected by libration. The shortest Au ··· Au contacts between molecules are 338 pm.

Some new conducting solids of the general formula Z x M(C 3 S 5 ) 2 and its selenium analogs (where: Z = Bu 4 N, Na, Li, NH 4 ; M = Ni, Pd, Pt etc.; 0 < x ≤ 1) were prepared and studied.

The crystalline black polymeric Cu I complex CuBr · S 4 N 4 can be prepared in high yield from Cu(NO 3 ) 2 · 3 H 2 O, NH 4 Br and S 4 N 4 in methanol. An X-ray structure analysis shows that it is isostructural with CuCl · S 4 N 4 . The crystals contain [CuBr] ∞ chains and the Cu atoms of adjacent chains are bridged by S 4 N 4 groups. The Cu atoms have an almost tetrahedral coordination. The 1,3-N,N′-bonded S 4 N 4 group has the same conformation and, within narrow limits, the same dimensions as free S 4 N 4 . Thermolysis of CuBr · S 4 N 4 at 180 °C yields among other products CuBr, S 4 N 4 , and S 2 N 2 .

The perovskite-related cyano compounds CsM II Cr(CN) 6 (M II = Mn, Zn), CsZnFe(CN) 6 and CsMnCo(CN) 6 (Mn = Mn-Cu) are characterized by their IR active C - N and M III -CN stretching frequencies, their lattice constants and their magnetic susceptibilities (4,2-295 K). Except for CsCuCo(CN) 6 , which is tetragonally distorted, all compounds crystallize cubically face-centered (with lattice constants in the range from 1020 to 1084 pm). The magnetic behaviour indicates low spin M III and high spin M II states, supporting the IR evidence for a strictly ordered M III -CN-M II arrangement. The compound CsMnCr(CN) 6 is ferrimagnetic, with a Néel temperature of T N = 90 K and an extrapolated spontaneous magnetization of a = 2,30 μ B at 0 K. Superexchange interactions via the cyano bridges are considered responsible for the ferrimagnetism observed.

On chemical, IR and 1 H NMR spectroscopic evidences the structure of the so-called sulfurylindoxyl was found to be 2-aminophenyl methyl sulfone (4) and not the benzo-thiazoline-1,1-dioxide (7) claimed by Claasz [1]. Contrary to data in the literature [2] the title compound gives only one sort of monoacetyl derivatives: 2-acetamidophenyl methyl sulfone (10). An unambiguous synthesis of 3-acetylbenzothiazoline-1,1-dioxide (8) is presented.

By reaction of M(CO) 6 (M = Cr, Mo, W) with the bifunctional aminophosphane Ph(NEt 2 )P-(CH 2 ) 4 -P(NEt 2 )Ph (L-L) octahedral complexes (CO) 4 M cis(L-L) are obtained. While it is shown by 31 P{ 1 H} NMR spectroscopy, that these complexes contain meso-and rac-(L-L) to a different extent, there is evidence from 13 C{ 1 H} NMR data obtained for the Mo complex, that the rac-ligand always prevails. As racemisation is observed when the Mo complex reacts with HBr to give (CO) 4 Mo-cis[Ph(Br)P-(CH 2 ) 4 -P(Br)Ph] an S N 1 -mechanism is suggested for this reaction.

The reaction of the sodium carbonyl metalate Na[W(CO) 3 Cp] with the phosphorane (Me 3 SiCH 2 ) 3 PBr 2 results in the formation of (Me 3 SiCH 2 ) 3 PandCp(CO) 3 WBr or [Cp(CO) 3 W] 2 , respectively, depending on the solvent used. The redox reactions between Na[Mo(CO) 3 Cp] and the arsenic analogue (RCH 2 ) 3 AsBr 2 (R = Ph, Me 3 Si) yield the products Cp(CO)sMoBr and (RCH 2 ) 3 As. A mechanism involving radicals is discussed. At elevated temperatures the products react further to give the square pyramidal complexes cis-Cp(CO) 2 [As(CH 2 R) 3 ]MBr (1, 2a, b) with loss of CO. In an analogous manner Cp(CO) 3 MBr (M = Mo, W) and (RCH 2 ) 3 E (E = As, Sb) afford compounds cis-Cp(CO) 2 [E(CH 2 R) 3 ]MBr (2c, 3). The dynamic behaviour of the chiral complexes 1, 2a, b, was investigated by 1 H NMR spectroscopy.

The preparation of the title aldehydes 1 and 6 a, the corresponding alcohols 2 a and 6 b and some other derivatives is described.

The title compound 9, C 38 H 62 , was prepared by dehalogenation of 2,4,6-tri-tert-butyl-benzyl chloride (7a). It crystallizes in the monoclinic space group C2/c with Z = 4. a = 10.923(7), b = 17.910(3), c = 17.395(3) Å and β = 91.87(3)° (the cell constants refer to 173 K). The structure was solved by direct methods and refined by full-matrix least squares to R = 0.073 for all 3853 reflexions (|F 0 | > 0). On account of steric repulsions, the central ethane bond, which lies on a twofold crystallographic axis, is stretched to 1.567(4) Å. Close packing of the molecules in layers parallel the ac-plane leads to boat-deformations of the benzene rings. Room-temperature data sets of weakly diffracting crystals [a = 10.948(6), b= 17.97(1), c= 17.52(2) and β = 91.9(1)°] do not give rise to an artificial shortening of the central ethane bond of 9. Evidently, poor data quality or lack of resolution have not to be considered as an explanation for the unusual short ethane bond [1.47(3) Å] in the first undamped hexaphenylethane [Stein, Winter, and Rieker (1978)].

The stable ternary copper(II) complexes of ATP and ADP, [Cu(H 2 ATP)(phen)] 2 · 7 H 2 O (2) and [Cu 4 (HADP) 2 (bipy) 4 (H 2 O) 2 (NO 3 ) 2 ] · 2 NO 3 (3), have been isolated from aqueous solution at respective pH values of 2.8 and 4.0. Their structures have been established by single crystal X-ray diffraction. Tridentate coordination of each of the Cu atoms by ono α-, one β- and one γ-phosphate O atom of one ATP molecule is observed in 2. The binding O α atoms occupy axial positions in a distorted octahedral geometry at Cu and the Cu- O α interactions are weak. The other axial position is occupied by a γ-phosphate O atom of the second ATP molecule, leading to a dimeric structure. The basic structure of 3 is similar with, in this case, bidentate coordination of each of the central Cu atoms by one α- and one β-phosphate O atom of ono ADP molecule. In this case, however, the third terminal β-phosphate O atoms each bind a further Cu atom. All four Cu atoms in 3 display square pyramidal coordination. The structures of 2 and 3 are stabilised by intramolecular stacking of adenine and phenanthroline/bipyridyl systems. The significance of these structures as models for enzyme-metal ion-nucleoside polyphosphate complexes is discussed.

[N-Ac-Thr 1 ,D-Phe 2 ,D-Trp 3,6 ]-LHRH was the model antagonist of LHRH, which was the basis for tho design, synthesis and bioassay of seven peptides having four, five and six D-amino acids, which resulted from three single, three double, and one triple introductions of D-amino acids in positions 4, 5 and 8 of the model. Only the analog with six D-amino acids, [N-Ac-Thr 1 ,D-Phe 2 ,D-Trp 3 ,D-Ser 4, D-Tyr 5 ,D-Trp 6 ,D-Arg 8 ]-LHRH, had antiovulatory activity which was higher than that of the model antagonist, i.e., 70% antiovulatory activity at 25 μg/rat compared with 50% activity at 50 μg/rat, respectively. Empirical energy calculations gave a conformational structure for [N-Ac-Thr 1 ,D-Phe 2 ,D-Trp 3 , D-Ser 4 ,D-Tyr 5 ,D-Arg 6 ,D-Arg 8 ]-LHRH which is similar to that calculated for previous potent antagonists. These results are a basis of new designs of antagonists having D-sub-stituents in up to ten positions toward effective inhibitors of ovulation by the parenteral and oral routes of administration.

From the culture medium of Pseudomonas cepacia 2-(o-hydroxyphenyl)-thiazol and its 4-carbaldehyd and 4-carboxylic acid derivatives (aeruginoic acid) could be isolated. Their structures were elucidated and confirmed by synthesis.

The reaction of 6-amino-6,7-dihydro-5H-dibenzo[c,e]azepine, bearing a terminal blocking group, with trifluoracetylnitrite presumably proceeds via cyclic 7-membered N-diazonium ions and mainly leads to the formation of phenanthridine by migration of the aryl group. 5H-Dibenzo[c,e]azepine can be isolated as the minor product and seems to be the result of a hydrogen shift. N ,N′-Azo-6,7-dihydro-5H-dibenzo[c,e]azepine dis-plays an analogous behaviour.

L-Homoserine was tritylated via its silylated product with Me 2 SiCl 2 or Ph 2 SiCl 2 in 65-68% yield. Also N-Trt-L-methionine upon treatment with Mel and degradation of the resulting sulfonium salt with KOH yielded N-Trt-L-homoserine in 75% yield. Both routes provided N-Trityl-L-homoserine with identical physical data. In contrast to N-alkyloxycarbonyl-L-homoserine derivatives, N-Trt-L-homoserine shows no tendency to spontaneous lactonization.

A number of O-(triphenylstannyl)-N-acyl-N-arylhydroxylamines have been synthesized. Results of IR, electronic (UV) and 1 H NMR spectroscopic measurements suggest that these compounds possess trigonal bipyramidal configuration around a pentacoordinated tin atom with phenyl groups cis to each other.

The reaction of diosgenin (1) with hydrogen peroxide/formic acid was investigated. As a result of this work, 5 α (25 R)-spirostane-3 β,5,6 β-triol (2) was prepared in 79% yield and 5 α-pregnane-3 β,5,6 β,16 β,20 α-pentol (3) in 80% yield. The pentol (3) was oxidised to 5 α-pregnane-3 β,5,10 β,20 α-tetrol-6-one (5) without forming its 16 β,20 α-isopropylidenedioxy derivative (4). Reaction of product 5 with CH 3 Mgl to give 6-methylpregnane derivative was unsuccessful. Therefore, product 7 was oxidatively degraded by H 2 O 2 /HCOOH to the 10-keto pregnane derivative (13) and its structure was proved through its transformation to 6 β-methylpregn-4-ene-6 α,20 α-diol-3,16-dione (15).

2-(1,2,4-Oxadiazol-5-yl)vinylphosphates and 2-(1,2,4-thiadiazol-5-yl) vinylphosphates are prepared from the corresponding chlorophosphates and 5-acetonyl-1,2,4-oxadiazoles and 5-acetonyl-1,2,4-thiadiazoles resp. Some of the oxazolylvinylphosphates are effective insecticides and acaricides, but the corresponding thiadiazole derivatives have almost no effect.

Triazolyloximinoethers are fungicides with high activity. Methods for the synthesis of these compounds and their stereochemistry are reviewed.

Quinazolines are fungicides with high activity. Methods to synthesis these compounds are reviewed.

Derivates of phenoxyphenoxypropionic Acids are herbicids with high activity. Methods to synthesis these compounds are reviewed. Relationship between structure and herbicidal activity are discussed.

Pyrethroids are known insecticides with a great potency to a wide range of insect species. Derivatizations at the benzylic position and at the second aromatic ring system of these pyrethroids yielded new benzylic esters with insecticidal activity. Methods for the synthesis of these compounds are reviewed.

By the react ion of mercuric chloride and hexamethylenetetramine in aqueous solution crystals of the title compound could be obtained. The compound contains planar trichloromercurate (II) anions; in the crystal they form infinite chains, interlinked by chloride bridges.

2,4′-Oxybispyridine is synthesised by reacting 4-nitropyridine with the silver salt of 2-hydroxy-pyridine.

The pungent odours emitted by true bugs when disturbed have captured the attention of numerous students of the Heteroptera. Studies of the chemical composition of the secretion of these stink bugs have shown the presence of alkanes, alkenyl acetates, alcohols and unsaturated aldehydes [1-3]. Most of these chemicals are employed as chemical warfare against the onslaught of microbial, vertebrate and in-vertebrate attackers [4], We herein report the chemical investigation of a previously unstudied secretion of a pentatomid bug, Aspavia brunna. The combined gas chromatography -mass spectrometry provides an excellent method for the study of the secretions of insects. We have utilized this technique and our results are summarized below.