Reaktionen an komplexgebundenen liganden: XXIX. Ein einfacher weg zu azomethin-komplexen: Kondensation von chrom—, molybdän—, wolfram—, mangan— und eisen—ammoniak-komplexen und ketonen zu ketimin-komplexen

Treatment of transition-metal—ammonia complexes with ketones yields complexes with RR′CNH ligands. Of particular interest is the stabilization of dialkylketimines such as e.g. (CH₃)₂CNH and C₆H₁₀NH in [M(CO)₅{NHC(CH₃)₂}] or [M(CO)₅ {NHC₆H₁₀}] (M = Cr, Mo, W). The principle of synthesis may be applied to a wide range of different metals and types of complexes, as can be shown by the synthesis of [C₅H₅Mn(CO)₂ {NHC(CH₃)₂}], [C₅H₅Fe(CO)₂{NHC(CH₃)₂}]PF₆, [M(CO)₄L₂] (M = Cr, Mo, W; L = (CH₃)₂CNH, C₆H₁₀NH) and [W(CO)₃(diphos){NHC(CH₃)}₂]. Treatment of [Cr(CO)₅NH₃] with urotropine gives [Cr(CO)₅ {N₄(CH₂)₆}] which is also obtained from [Cr(CO)₅THF] and urotropine. The methods of preparation, reactions and spectroscopic properties of the complexes are reported.     

Reactions of perfluoronitriles. III. Interactions with diphenylphosphine

Reaction of perfluoro-n-octanonitrile with diphenylphosphine gave two products: a primary adduct, C₇F₁₅C(NH)P(C₆H₅)₂, and the reduced adduct, C₇F₁₅CH(NH₂)P(C₆H₅)₂. Presence of water prevented the formation of the reduced compound; the latter was not produced by reduction of the primary adduct. Operative mechanisms are postulated; infrared and mass spectra are discussed.     

Asymmetrically substituted ferrocene derivatives showing redox switching of optical properties

The electrochemical and spectroelectrochemical behaviors of three ferrocene derivatives, (1) (C₁₈H₃₇)₂NC₆H₄CHCHFcCH₂OH, (2) (C₁₈H₃₇)₂NC₆H₄CHCHFcCHO, (3) (C₁₈H₃₇)₂NC₆H₄CHCHFcCHC(CN)₂, were studied and analyzed on basis of frontier orbital interactions. It was shown that all the three derivatives show two oxidation steps. The first oxidized states of 1 and 2 are stable and show strong LMCT (ligand-to-metal charge transfer) bands. This suggests that they may serve as redox switching of optical properties. In contrast, the first oxidized state of 3 becomes unstable due to strong electron-withdrawing effect of the acceptor substitute.     

Preparation of new 2‐amino‐ and 2,3‐diamino‐pyridine trifluoroacetyl enamine derivatives and their application to the synthesis of trifluoromethyl‐containing 3H‐pyrido[2,3‐b][1,4] diazepinols

The synthesis of a novel series of the intermediates N²(N³)‐[1‐alkyl(aryl/heteroaryl)‐3‐oxo‐4,4,4‐trifluoroalk‐1‐en‐1‐yl]‐2‐aminopyridines [F₃CC(O)CH?CR¹(2? NH?C₅H₃N)] and 2,3‐diaminopyridines [F₃CC(O)CH?CR¹(2‐NH₂‐3‐NH? C₅H₃N)], where R¹ = H, Me, C₆H₅, 4‐FC₆H₄, 4‐CIC₆H₄, 4‐BrC₆H₄, 4‐CH₃C₆H₄, 4‐OCH₃C₆H₄, 4,4′‐biphenyl, 1‐naphthyl, 2‐thienyl, 2‐furyl, is reported. The corresponding series of 2‐aryl(heteroaryl)‐4‐trifluoromethyl‐3H‐pyrido[2,3‐b][1,4]diazepin‐4‐ols obtained from intramolecular cyclization reaction of the respective trifluoroacetyl enamines or from the direct cyclocondensation reaction of 4‐methoxy‐1,1,1‐trifluoroalk‐3‐en‐2‐ones with 2,3‐diaminopyridine, under mild conditions, is also reported.     

Allylstannation: II. A total “cis-preference” in the addition of n-Bu2ClSnCH(CH3)CHCH2 to aldehydes

1-Buten-3-yldi-n-butylchlorotin, formed by redistribution of ($\text{E}\text{Z}$)-2-butenyltri-n-butyltin and Bu₂SnCl₂, reacts readily with neat RCHO (R  C₂H₅, C₂H₅(CH₃)CH, (CH₃)₂CH, (CH₃)₃C and C₆H₅) to give high yields (80–100%) of alcohols of the type RCH(OH)CH₂CHCHCH₃ only in the Z-configuration. This appears to be the first example of total “cis-preference” in the addition of Grignard-like reagents to carbonyl compounds. The results are discussed in terms of steric requirements around the tin centre which is probably five-coordinate in the transition state.     

Some approaches to the synthesis of fluorinated alcohols and esters. II. Use of F-alkyl iodides for the synthesis of F-alkyl alkanols

Free radical addition of an F-alkyl iodide (R_FI) to an alkenol or ester, followed by appropriate reduction is an efficient method for preparing the corresponding F-alkyl-alkanols of the homologous series, R_F(CH₂)_n?OH. When n = 2,4 or higher, the two steps take place smoothly. The 1,2,3-substituted systems R_FCH₂CHYCH₂Z, however, are susceptible to surprising difficulties. Reduction of R_FCH₂CHICH₂ON to R_F(CH₂)₃OH by hydrogen and catalyst (strong base acid acceptor), can be done either in one step or $\text{via}$ R_FCHCHCH₂OH; however, dehydrohalogenation may also give the epoxide, and reduction in this case leads to the secondary alcohol, R_FCH₂CH(CH₃)OH. By contrast, reduction of R_FCH₂CHICH₂OAc by tributyltin hydride or with hydrogen over palladium (diethylamine acid acceptor) goes smoothly. Zinc and acid reduction of R_FCH₂CHICH₂OAc gives elimination to R_FCH₂CHCH₂; even R_FCHCICH₂OH gives R_FCHCCH₂ besides R_FCHCHCH₂OH. R_FCHCICH₂CH₂OH, however, with zinc and acid is reduced cleanly to R_FCHCHCH₂CH₂OH.     

Past,present and future of the clathrate inclusion compounds built of cyanometallate hosts

One-, two- and three-dimensional CN-bridged metal complex structures made up of building blocks such as linear [Ag(CN)₂]^–, square planar [Ni(CN)₄]^2– or tetrahedral [Cd(CN)₄]^2–, and of the complementary ligands such as ammonia, water, unidentate amine, bidentate a,w- diaminoalkane, etc., are reviewed with an emphasis on their behaviour as hosts to afford clathrate inclusion compounds with guest molecules and as self-assemblies to form supramolecular structures with or without guests. The historical background is explained for Prussian blue and Hofmann's benzene clathrate based on their single crystal structure determinations. The strategies the author and coworkers have been applying to develop varieties of clathrate inclusion compounds from the Hofmann-type are demonstrated with the features observed for the developed structures determined by single crystal X-ray diffraction methods.Abbreviations for Ligands and Guests mma NMeH₂ - dma NMe₂H - tma NMe₃ - mea NH₂(CH₂)₂OH - en NH₂(CH₂)₂NH₂ - pn NH₂CHMeCH₂NH₂ - tn NH₂(CH₂)₃NH₂ - dabtn NH₂(CH₂)₄NH₂ - daptn NH₂(CH₂)₅NH₂ - dahxn NH₂(CH₂)₆NH₂ - dahpn NH₂(CH₂)₇NH₂ - daotn NH₂(CH₂)₈NH₂ - danon NH₂(CH₂)₉NH₂ - dadcn NH₂(CH₂)₁₀NH₂ - mtn NMeH(CH₂)₃NH₂ - dmtn NMe₂(CH₂)₃NH₂ - detn NEt₂(CH₂)₃NH₂ - temtn NMe₂(CH₂)₃NMe₂ - dien NH₂(CH₂)₂NH(CH₂)₂NH₂ - pXdam p-C₆H₄(NH₂CH₂)₂ - rnXdam m-C₆H₄(NH₂CH₂)₂ - py C₅H₅N pyridine - ampy NH₂C₅H₄N aminopyridine - Clpy CIC₅H₄N chloropyridine - Mepy MeC₅H₄N methylpyridine - dmpy Me₂C₅H₃N dimethylpyridine - bpy NC₅H₄C₅H₄N bipyridine - quin C₇H₉N quinoline - iquin iso-C₇H₉N isoquinoline - qxln C₈H₆N₂ quinoxaline - Pe C₅H₁₁-pentyl imH: C₃N₂H₄ imidazole - pyrz N(CHCH)₂N pyrazine - Mequin MeC₇H₈N methylquinoline - bppn C₁₃H₁₄N₂ 1,3-bis(4-pyridyl)propane - bpb C₁₄H₈N₂ 1,4-bis(4-pyridyl)butadiyne - N-Meim C₃N₂H₃Me N-methylimidazole - 2-MeimH C₃N₂H₃Me 2-methylimidazole - dmf HOCNMe₂ dimethylformamide - hmta C₆H₁₂N₄ hexamethylenetetramine - o-phen C₁₂H₈N₂ 1,10-phenanthroline - den HN(CH₂CH₂)₂NH piperazine - morph HN(CH₂CH₂)₂O morpholine - ten N(CH₂CH₂)₃N 1,4-diazabicyclo[2.2.2]octane - ameden NH₂(CH₂)₂N(CH₂CH₂)₂NH N-(2-aminoethyl)piperazine Presented at the Sixth International Seminar on Inclusion Compounds, Istanbul, Turkey, 27–31 August, 1995.     

Metal–azo and metal–imine compounds II. : II. Insertion of Ir1 into aromatic and olefinic CH bonds

The reaction of the aromatic azo or imine compounds PhX=NR (X=N or CH; R = alkyl or aryl) and 2-(methylazo)propene, H₂CC(CH₃)N&.zdbnd;NCH₃, with trans-IrCl(N₂)(PPh₃)₂ yields the (ortho) metallated complexes IrHCl(G₆H₄X=NR)(PPh₃)₂ and IrHClCHC(CH₃)-NNCH₃](PPh₃)₂ respectively.The v(N=N) vibration in IrHCl(C₆HZ₄N=NPh)(PPh₃)₂ appears to be drastically lowered with respect to the free ligand vibration. Furthermore, Resonance Raman experiments show that this vibration is strongly coupled to both of the electronic transitions of this compound at longer wavelengths, which therefore must be closely connected with the azo group.¹H and ¹³C NMR spectroscopic data and crystallographic studies of IrHCI(C₆H₄N=NPh)(PPh₃)₂ give strong evidence about the nature of the mechanism of these (ortho) metallation reactions.     

Transition metal complexes of azo compounds V. Complexation and cleavage of the NN bond of diazirines by iron carbonyls

3,3-Dimethyldiazirine and 3,3-pentamethylenediazirine, R₂CN₂, react with enneacarbonyldiiron initially via N-tetracarbonyl intermediates to give dark blue μ-1,2-diazirine-bis(tetracarbonyliron) complexes and small amounts of an Fe₃(CO)₉-cluster of the diazirine. Depending upon the solvent, further reaction may take place by splitting of the NN bond to yield orange (R₂CN)Fe₂(CO)₆(NCR₂) and red (R₂CN)Fe₂(CO)₆(NCO), which contain bridging ketiminato and isocyanato groups. Formation of the latter complexes probably involves “nitrenic” intermediates. A general scheme is proposed for the reactions of the cis-azo group of cyclic azo compounds with iron carbonyls which permits estimation of the product ratio as a function of the ring size of the parent azo ligand. (R₂CN)Fe₂(CO)₆(NCO) adds methanol at room temperature to give (R₂CN)Fe₂(CO)₆(NHCO₂Me).     

Darstellung von polyfluororganotrichlorsilanen

The following substances could be prepared by Grignard reactions or by conversions with trichlorosilane: C₆F₅CH₂CHCH₂, C₆F₅(CH₂)₃SiCl₃, CF₃(CF₂)₉CH₂CHCH₂, CF₃(CF₂)₇(CH₂)₂SiCl₃, CF₃(CF₂)₁₁(CH₂)₃CHCH₂ und CF₃(CF₂)₁₁(CH₂)₅SiCl₃.They were characterized by spectroscopical and microanalytical methods.     

Ringöffnende acetylierung eines an kobalt koordinierten ringliganden vom divinylboran-typ

(C₅H₅)Co[2–6-η-(CH₃)₂Si(CHCH)₂BC₆H₅(III) is prepared photochemically from (C₅H₅)Co(CO)₂ and (CH₃)₂Si(CHCH)₂BC₆H₅ (II). Acetylation of the new complex III with CH₃COCl/AlCl₃ and subsequent hydrolysis effect ring-opening new complex III with CH₃COCl/AlCl₃ and subsequent hydrolysis effect ring-opening to give (C₅H₅)Co[(1,2-η-(cis-CH₃COCH)CH(η-CH₂CH)Si(CH₃)₂] (IV) which slowly isomerizes (ΔG^≠₂₉₆ 100 ± 2 kJ mol^?1) to the corresponding trans-isomer (V).Pure (CH₃)₂Si(CHCH)₂Sn(CH₃)₂ (I) can be obtained in preparative quantities via the new complex (CH₃)₂Si(CHCH)₂Sn(CH₃)₂ · 2 CuCl.     

The Reactions of Two New Alkoxy-silyl Functionalized Alkynes with M<Subscript>3</Subscript>(CO)<Subscript>12</Subscript> {M = Fe,Ru} and Co<Subscript>2</Subscript>(CO)<Subscript>8</Subscript>. Spectroscopic Identification of the Products

The new alkoxysilyl-functionalized alkynes [HC≡CCH₂N(H)C(=O)N(H)(CH₂)₃Si(OEt)₃] and [HC≡C(C₆H₄)–N(H)C(=O)N(H)(CH₂)₃Si(OEt)₃] have been synthesized using literature methods. These have been reacted with Fe₃(CO)₁₂, Ru₃(CO)₁₂ and Co₂(CO)₈. With the iron carbonyl only decomposition was observed: with Ru₃(CO)₁₂ splitting of the alkynes into their parent components and formation of the complexes (μ-H)Ru₃(CO)₉[HC=N(CH₂)₃Si(OEt)₃], (μ-H)Ru₃(CO)₉[C–C(C₆H₄)NH₂] and (μ-H)₂Ru₃(CO)₉[HC–CCH₃] occurred. Finally, with Co₂(CO)₈ formation of complexes Co₂(CO)₆(HC₂R) R=(C₆H₄)NH₂, CH₂NH(CO)NH(CH₂)₃Si(OEt)₃, (C₆H₄)NH(CO)NH(CH₂)₃Si(OEt)₃ containing the intact alkynes could be obtained.     

High-yield catalytic metathesis of alkenyl tosylates with applications in organic synthesis

Alkenyl tosylates of the type RCHCH(CH₂)_nOTs [RH, n=9; RH, n=7; and RCH₃(CH₂)₇, n=8] undergo metathesis using a WCl₆-Me₃SnCl catalyst system, producing difunctionalised alkenes of the type TsO(CH₂)_nCHCH(CH₂)_nOTs (n=7,8, and 9); examples of the use of these products in synthesis are presented.     

Alkylsilver(I) induced 1,5-substitution in functionally conjugated enynes. a novel route to cumulated trienes

Functionally conjugated enynes, H₂CC(R¹)CCCR²R₃OS(O)Me, undergo 1,5-substitution with alkylsilver(I) reagents, RAGG ☆ 3 LiBr. The purity of the produced alkylated butatrienes, RCH₂C(R¹)CCCR²R³ depends on the nature of R in RAg ☆ 3 LiBr and on the substituents R¹, R² and R³ in the substrate.     

Alkaline hydrolysis of diaryl ditellurides under phase transfer conditions; synthesis of alkyl aryl tellurides

The disproportionation reaction of diaryl ditellurides [(C₆H₅Te)₂, (p-CH₃C₆H₄Te)₂, (p-CH₃OC₆H₄Te)₂, (p-C₂H₅OC₄Te)₂, (2-naphthyl-Te)₂] with sodium hydroxide under phase transfer conditions at room temperature is described for the first time. The phase transfer catalyst used is 2HT-75, a trade name for a mixture of dialkyldimethylammonium chlorides. The intermediates aryl tellurolates react “in situ” with alkyl halides to give the corresponding alkyl aryl tellurides (ArTeR) in 52–72% yield. The following compounds were prepared: Ar  C₆H₅, R=CH₃(CH₂)₃CH₂, (CH₃)₂CHCH₂CH₂, (CH₃)₂CHCH₂, CH₃CHBrCH₂CH₂, CH₃(CH₂)₈CH₂, C₆H₅CH₂, ClCH₂, C₆H₅CH₂CH₂, CH₂CHCH₂, C₆H₅CHCHCH₂, C₆H₅SeCH₂, $\text{CH}{}_2\text{CH}{}_2\text{CH}{}_2\text{CHCHC}$H; Ar=p-CH₃C₆H₄, R = CH₃(CH₂)₂CH₂; Ar=p-CH₃OC₆H₄, R = CH₃(CH₂)₂CH₂; Ar = p-CH₂H₅OC₆H₄, R= CH₃(CH₂)₂CH₂; Ar = 2-naphthyl, R = CH₃(CH42)₂CH₂.     

1-Alkoxy-2-azaallenyl-komplexe von chrom und wolfram

The successive reaction of (CO)₆M with Na[NCR₂¹] and [Et₃O]BF₄ yields (CO)₅M[C(NCR₂¹)OEt] (II: M = Cr; III: M = W; CR₂¹ = C(C₆H₄Br-p)₂ (a), CPh₂ (b), C(C₆H₄OMe-p)₂ (c), C(C₆H₄)₂O (d), CBu₂^tt (e)). Hexacarbonyltungsten, (CO)₆W, reacts with Na[NCPh₂] and MeOSO₂F to give (CO)₅W[C(NCPh₂) OMe] (IV). X-Ray analysis of IIe shows that: (1) the CNC fragment is almost linear (171.7°); (2) the two NC bond lengths are equal within experimental error; and (3) the O,C,Cr,N plane is perpendicular to the C(Me₃),C,N,C(Me₃) plane (90.0°). Therefore compounds II–IV are best described as 1-alkoxy-2-azaallenyl complexes.     

Funktionell substituierte zinnorganische verbindungen v. st]Phosphono- Und phosphonylmethyl-triorganostannane

The synthesis of phosphono- and phosphonylmethyl-triorganostannanes R₃SnCH₂P(O)(OR′)R′′ (R′′  OR′, C₆H₅) via an Arbuzov reaction of R₃SnCH₂I with P(OR′)₃ or C₆H₅P(OR′)₂ (R′′  CH₃, C₂H₅) is described. The new compounds have been studied with regard to their behaviour towards electrophilic (Br₂, HCl, HgBr₂) and nucleophilic (NaOH, LiAlH₄, LiR) agents. Their reaction with chlorophenylphosphines followed by reduction with LiAlH₄ yields the unsymmetrical methylenebis(phosphines) C₆H₅P(R)CH₂PH₂ (R  H, C₆H₅). The title compounds add to the carbonyl group of aldehydes and the CN bond of phenylisocyanate.     

Novel heterocyclic selenazadiphospholaminediselenides, zwitterionic carbamidoyl(phenyl)-phosphinodiselenoic acids and selenoureas derived from cyanamides

2,4-Bis(phenyl)-1,3-diselenadiphosphetane-2,4-diselenide (Woollins’ reagent, WR) reacts with cyanamides (1a-h) in refluxing toluene to afford a series of novel selenazadiphospholaminediselenides (RR′NCN(PhP(Se)SeP(Se)Ph, R=C₆H₅(CH₂)_1-3, 4-n-C₁₀H₂₁C₆H₄ and 4-BrC₆H₄CH₂; R′=H, CH₃, C₂H₅ and C(O)OC₂H₅2a-g). Post-treatment of the reaction mixture with water led to the formation of carbamidoyl(phenyl)phosphinodiselenoic acids (RR′NC(NH₂)P(SeH)₂Ph, R=C₆H₅(CH₂)_2-3, 4-n-C₁₀H₂₁C₆H₄ and 4-BrC₆H₄CH₂; R′=H and CH₃, 3b, 3c, 3e and 3f) and selenoureas (RR′NC(Se)NH₂, R=C₆H₅(CH)_1-2; R′=CH₃ and OC(O)C₂H₅, 4f and 4h) in moderate to excellent yields. All new compounds are characterised spectroscopically and five X-ray crystal structures are reported.     

Action des perfluoroalkylcuivre(I) sur les perfluoroalkylethylenes

A series of new polyfluorinated dienes 3, containing the novel -CFCHCHCF-, pattern has been synthesized (50–70% yields) by reacting perfluoroalkyl iodides with perfluoroalkyl-ethylenes in the presence of copper. The monoalkenes R_fCFCHCH₂CF₂R′_f and the saturated compounds R_fCF₂CH₂CH₂CF₂R′_f were obtained by varying the experimental conditions. The ¹H and ¹⁹F NMR spectra are analysed and the reaction mechanism is discussed.     

Kinetics of hydrolysis of amino acid esters in the presence of aquocomplexes involving ethylenediamine,diethylenetriamine and triethylenetetramine ligands. Part 2. Cobalt(II), cobalt(III), platinum(II) and palladium(II)

Summary Aquocomplexes of cobalt(II), cobalt(III), palladium(II) and platinum(II) involving (H₂NCH₂)₂, [H₂N(CH₂)₂]₂NH and [H₂N(CH₂)₂NHCH₂]₂ as ligands were prepared and characterized. The kinetics of base hydrolysis of the amino acid esters H₂NCH₂CO₂Me·HCl, HOC₆H₄CH₂CH (NH₂)CO₂Me·HCl, MeS(CH₂)₂CH(NH₂)CO₂Me·HCl, HSCH₂CH(NH₂)CO₂Et·HCl, C₃H₃N₂CH₂CH(NH₂)-CO₂Me·2HCl and [—SCH₂CH(NH₂)CO₂Me]₂·2HCl in the presence of these complexes have been studied. The rate of hydrolysis is influenced substantially by these complexes and the second order rate constants are some 10–90 times greater than those obtained in the presence of simple metal ions.