Search

Ultrasound-induced Synthesis of Trimethylsilylacetic Acid Trimethylsilylester. The reaction of bromoacetic acid trimethylsilylester with zinc in presence of chlorotrimethylsilane is promoted by sono-waves. The trimethylsilylacetic acid trimethylsilylester could be obtained in high yield. Different products are observed in presence of dichloro dimethylsilane. Mechanical aspects are discussed.

Bis-(o-halophenoxy)silane reagieren mit Natrium nach Metallierung im Sinne einer raschen intramolekularen [1,3]-carbanionischen Umlagerung zu den Natriumsalzen der Bis-(o-hydroxyphenyl)silane (R1R2Si(o-C6H4ONa)2; R1 = Me, OMe…). Diese lassen sich durch Protolyse in die freien Phenole uberfuhren oder im Eintopfverfahren mit reaktiven Halogenverbindungen verestern und verethern. [1.3]-Carbanionic Rearrangements. Synthesis of Bis-(o-hydroxyphenyl) silane Derivatives Bis-(o-halophenoxy)silanes react via metallation in a fast two step [1.3]-carbanionic rearrangement to the sodium salts of the bis-(o-hydroxyphenyl)silanes (R1R2Si(o-C6H4ONa)2; R1 = Me, OMe…). These are protolyzed to the free phenols or are giving ethers and esters by reacting with reactive halogen compounds in an one pot reaction.

The synthesis of bis(organostannyl)ethanes of the types (Ph 2 XSnCH 2 ) 2 ( 1 , X = Ph; 2 , X = Cl; 3 , X = Br; 4 , X = I) and (Ph 2 XSnCH 2 ) 2 ( 5 , X = Br, 6 , X = I) is described. The compounds have been investigated by means of 1 H, 13 C and 119 Sn NMR spectroscopy. 2 reacts with HMPA, [Ph 3 P = N = PPh 3 ] + Cl − , and Ph 4 PBr, respectively, to give the 1/1 complexes (Ph 2 ClSnCH 2 ) 2 · HMPA ( 7 ), [Ph 2 ClSnCH 2 ) 2 · Cl] − [Ph 3 PNPPh 3 ] + ( 8 ), and [(Ph 2 ClSnCH 2 ) 2 · Br] − [Ph 4 P] + ( 9 ). The formation constant K a for 8 in CDCl 3 solution is 2260 M −1 . The structures of 7 and 8 have been determined by X-ray diffraction. That of 7 shows that the two tin atoms are pentacoordinate but are inequivalent as a result of having different coordination sphere; one tin atom is coordinated by the monodentate HMPA (SnO 2.255(3) A) whereas the other interacts with a bridging Cl (Sn(1); Cl(2) 3.000(1) A). In the anion of 8 , the bis(chlorodiphenylstannyl)ethane may be regarded as an unsymmetrical chelate ligand towards Cl(12) (Sn(1)-Cl(12) 2.83(1), Sn(2)-Cl(12) 2.70(1) A).

The synthesis of 1,1,6,6,11,11-hexamethyl-1,6,11-tristannacyclopentadecane is reported. Its complexing ability for halide ions (Cl − , Br − ) is discussed and compared with that of the corresponding twelve-membered ring compound.

The reaction of N,N -bis(diphenylphosphinomethyl)amino acid derivatives with [Rh(dien)Cl] 2 yields six-membered chelate-rhodium complexes, which in hydrogenation reactions achieve optical yields of about 30% of α-acetamidocinnamic acid derivatives, independently of the amino acid used. The synthesis of the pre-catalysts and NMR studies of the in situ preparation show complex formation corresponding to the various solvents used. In polar solvents active catalysts are formed.

The compound pentacarbonyl-5-t-butyl-5-aza-2,8-dithia-1-stannobicyclo-[3.3.01,5]octanechromium(0) was prepared in good yield by the reaction of 5-t-butyl-5-aza-2,8-dithia-1-stannobicyclo[3.3.01,5]octane with Cr(CO)6 in THF under UV-irradiation. The crystal and molecular structure was determined from three-dimensional X-ray data. The crystals are monoclinic, space group P21/c. The unit cell, with dimensions a 14.963(9), b 10.026(5), c 13.565(5)Å, β 114.68°(5), contains 4 molecules. The structure was solved by the Patterson-method. The full-matrix refinement with the 2734 independent reflexions gave a final R value of 0.034. The eight-membered ring adopts an asymmetric boat-boat conformation with a tin-nitrogen bond lenght of 2.40 Å; the tin-chromium bond length is 2.62 Å.

α-Aminoacids, their esters and sodium salts may be transformed by a modified Mannich-reaction into N -phosphinomethyl or N,N -bis(phosphinomethyl) derivatives. The sodium or triethylammonium salts of the chiral bisphosphines l -()- N,N -bis(diphenylphosphinomethyl)-alanine and -valine may be used as ligands to form enantioselective hydrogenation catalysts with rhodium complexes. The highest optical yield achieved was 29%.

Phosphonic acid bis(o-haloarylesters) as well as the corresponding phosphoric acid derivatives are reacted with sodium giving bis(o- hydroxyaryl)phosphinoxides and phosphonic acid esters or amides, resp. The primary metallation products undergo rapid 1,3-carbanionic rearrangements. Magnesium may also be used as metallating agent if activated by means of anthracen in THF.

In contrast to arsabenzenes the π-excess aromatic 1H-1,3-benzazarsoles can be alkylated at the arsenic atom as well as lithiated in positions 1 or 2 without addition of LiN(i-Pr)2 and t-BuLi to the AsC (4p-2p)π bond. Alkylations and acylations of the ambident 1-lithio derivatives and substitution reactions of the 2-lithiobenzazarosole are described and the 1H and 13C NMR data of the compounds obtained are given.

Di-t-butylzinndimethoxid reagiert mit Organo-bis-o-hydroxy-phenyl-phosphinen RP(o-C6H4OH)2 in Benzen unter Austritt von Methanol zu den Titelverbindungen. Die Verbindungen sind monomer loslich, die Phosphor-Zinnkoordination wird 31P- und 119Sn-NMR-spektroskopisch nachgewiesen. 1-Organo-5,5-di-t-butyl-diptych-benzoxaphospha-stannolins — Diorganotin Compounds with Transannular SnP Interaction Di-t-butyltindimethoxid react with organo-bis-o-hydroxyphenyl-phosphines in benzene under elemination of methanol to the title compounds. The phosphorus-tin coordination is proved by 31 and 119Sn n.m.r. measurements.

The synthesis and structure of pentacarbonylmetal(0) complexes of the types (C0) 5 MSn(XCH 2 CH 2 ) 2 E (M = Cr, Mo, W; X = O, S; E = NR, PPh, O, S) and (CO) 5 WSn(SCH 2 CH 2 ) 2 E · py (E = NMe, O, S) are reported. 119 Sn and 13 C NMR studies show the compounds with X = O and E = NR to be dimeric whereas the derivatives with X = S have been found to be monomeric. The π-acceptor behaviour of the ligands Sn(XCH 2 CH 2 ) 2 E is comparable to that of the phosphanes. The barriers to internal rotations about the nitrogencarbon bonds have been determined for the NBu t derivatives.

1H, 13C, 15N and 119Sn NMR data for alkyl- and phenyl-stannatranes are reported. A trimeric structure and an intramolecular dynamic process are proposed.

The 1 H and 13 C NMR data for some N -methyl-5,5-dialkyldiptychthiaazstannolidines are reported. The differing coupling constants of the proton signals of the two nonequivalent Sn-alkyl groups suggest apical/equatorial positions for these groups at the pentacoordinated tin atom. The observed intramolecular process is explained by a dissociation-inversion mechanism.

The compound PhP(CH2CH2S)2SnCr(CO)5. C5H5N crystallizes in the triclinic space group P 1 with two molecules in a unit cell of dimensions a 10.654(2), b 10.146(3), c 12.448(3) A, α 85.31(2), β 79.66(2), γ 65.53(2)°, V 1204.8 A3. The structure was solved by the Patterson method. The full matrix refinement with the 4456 observed reflections gave a final R value of 0.034. The tin atom is pentacoordinated by 2S, Cr, N and P. The SnCr distance is 2.618 A, and the SnN and SnP donor-acceptor interactions are 2.514 and 2.756 A, respectively. The eight-membered ring adopts a boat-chair conformation.

The reactions of o -arsinophenoles with some carboxylic acid derivatives were studied. With imidoyl chlorides the aromatic 1,3-benzoxarsoles are obtained. The reaction proceeds via a primary attack of the arsino group. The spectroscopic data of the benzoxarsoles are discussed and compared with those of benzofurane, benzoxazole and corresponding NH-heterocycles.

o -Aminophenylarsine can be prepared in good yields by electrochemical reduction of o -nitrophenylarsonic acid. Its metallation and the reaction with alkyl halides yield the corresponding secondary o -aminophenylarsines. The As-metallated o -aminophenylarsines react with α-halocarboxylic acids to give α-( o -aminophenylarsino)carboxylic acids which cyclisize to tetrahydro-1,4-benzazarsenin-2-one. In an analogous reaction β-( o -aminophenylarsino)propionic esters can be obtained from o -aminophenylarsines and β-chloropropionic esters. The methyl ester of β-( o -aminophenylarsino)propionic acid reacts on heating to give tetrahydro-1,4-benz[ b ]methylazarsepin-2-one. All synthesized compounds have been characterized by chemical, NMR and mass spectroscopic methods.

α-Dialkylaminomethylphosphines and the corresponding arsines have been obtained by the following methods: (1) by direct Mannich reaction, (2) by reaction of secondary phosphines and arsines with bis(dimethylamino)methane, and (3) by reaction of methyleneammonium halides with secondary phosphines and arsines, silylphosphines and silylarsines, and alkali phosphides and alkali arsides, respectively. The compounds obtained show a similar reactivity as N,N-acetals. The aminomethyl group is transferred to H-acidic agents, the reaction with halides yields methylene ammonium halides and halophosphines or haloarsines, respectively. Reactivity towards methyl iodide is influenced by substituents at the phosphorus or arsenic atoms. In the case of the phosphorus compounds acetylphosphines are obtained by reaction with acetyl chloride, while the arsenic compounds add acetyl chloride to give ammonium salts.

The reaction of NaAsHR with ClCH 2 CH 2 CH 2 NH 2 yields the corresponding secondary 3-aminopropylarsines, RAs(H)CH 2 CH 2 CH 2 NH 2 , which with aldehydes and ketones form the perhydro-1,3-azarsenines. The properties and reactivity of these heterocyclic compounds are described.

The crystal and molecular structure of 5-t-butyl-5-aza-2,8-dithia-1-stanna(II)bicyclo[3.3.0 1,5 ]octane [Sn(SC 2 H 4 ) 2 NC 4 H 9 ] 2 have been determined from three-dimensional X-ray data. The crystals are monoclinic, space group P 2 1 / c , with cell dimensions: a 14.104(2), b 21.911(4), c 11.624(2) A, β 98.73(1)°, Z = 6. The final R is 0.040 for the 4279 observed reflections. The unit-cell contains four asymmetric dimers (dimer a ) and two centrosymmetric dimers (dimer b ), each dimer forms a four-membered Sn 2 S 2 ring in which the sulfur atoms are three-coordinated. The SnN distances in the two dimeric forms are significantly different (namely, 2.64 and 2.75 in dimer a , 2.97 A in dimer b ). The lengthening of the SnN distances involves the shortening of the bridging tin—sulfur bonds (2.99 and 2.79 in a , 2.71 A in b ). The coordination around the three different Sn atoms is hemispherical.

While o -substituted bromobenzene derivatives of the type o -BrC 6 H 4 XER n (X  O, S; ER n  SiMe 3 and N-BuLi undergo metal halogen exchange followed by silyl- X a C rearrangement, the corresponding compounds of phosphorus, arsenic or tin are split at the EX bond. o -Metal derivatives o -M 1 C 6 H 4 XER n (X  O, NMe; E  P, As, Sn) of these elements may be generated, however, by direct reaction with sodium or lithium. They are unstable and furnish o -hydroxy- and o -aminophenyl element(IV, V) derivatives via an intramolecular anionic rearrangement.

o -Aminophenylarsine reacts with iminoester hydrochlorides to give 1 H -1,3-benzazarsoles. The isomeric 3 H -1,3-benzazarsoles are synthesized from secondary o -aminophenylarsines and N -phenylimide chlorides. Spectroscopical studies show the 1 H -1,3-benzazarsoles to be genuine “arsaaromatics”.

The compound 1-aza-5-stanna-5-methyltricylo[3.3.3.01,5]undecane crystallizes in the space group P21c. The unit cell, with a 7.700(1), b 9.289(3), c 16.296(5) A, V 1159.4(5) A3, β 95.89(2)°, contains four molecules. The structure was refined to a final R value of 0.042. The configuration of the tin atom is intermediate between a trigonal bipyramid and a tetrahedron. The intramolecular tin−nitrogen distance is 2.624 A.

The title compounds are formed in the reaction of o-phosphinophenole with N-arylimide chlorides of carbonic acids. The primary adducts of formimmonium chlorides, however, undergo [2 + 2]-cycloaddition to furnish 1,3-diphosphetanes. A further way to 1,3-benzoxaphospholes consists in the cyclodehydratization of carbonic acid o-phosphinophenyl esters by means of P4O10.

o -Bromoaryl esters of phosphoric acid react with magnesium to give arene phosphonic acid derivatives via intermediate Grignard compounds. Similar metallation rearrangement processes may be achieved in the case of o -chloroaryl esters if sodium is applied as metal. 2,4-Dibromoaryl esters are attacked by magnesium regiospecifically in o -position.

Zusammenfassung 1,3-Benzoxaphospholes and 1,3-benzoxarsoles undergo Diels-Alder reactions with 2,3-dimethylbutadiene and formal [4+2]-cycloadditions with tetrachloro-o-benzoquinone.

The synthesis of phosphono- and phosphonylmethyl-triorganostannanes R 3 SnCH 2 P(O)(OR′)R′′ (R′′  OR′, C 6 H 5 ) via an Arbuzov reaction of R 3 SnCH 2 I with P(OR′) 3 or C 6 H 5 P(OR′) 2 (R′′  CH 3 , C 2 H 5 ) is described. The new compounds have been studied with regard to their behaviour towards electrophilic (Br 2 , HCl, HgBr 2 ) and nucleophilic (NaOH, LiAlH 4 , LiR) agents. Their reaction with chlorophenylphosphines followed by reduction with LiAlH 4 yields the unsymmetrical methylenebis(phosphines) C 6 H 5 P(R)CH 2 PH 2 (R  H, C 6 H 5 ). The title compounds add to the carbonyl group of aldehydes and the CN bond of phenylisocyanate.

Phosphinous acid o-bromoaryl esters or phosphorus acid o-haloaryl ester diamides react with sodium under mild conditions to give the corresponding sodium aryls which undergo rapid 1,3-carbanionic rearrangements to give o-phosphinophenolates. These may be worked up to the free phenoles or silylated by treatment with Me3SiCl.

5-Phenyl-5-phospha-2,8-dithia-1-stanna(II)bicyclo[3.3.o1,5]octane (1) was prepared in good yield by the reaction of tin(II) butoxide with the appropriate mercaptophosphane in toluene. Its crystal and molecular structure was determined by X-ray analysis. Compound 1 crystallizes in the rhombohedral space group R3, with 9 molecules in a unit cell of dimensions (referred to hexagonal axis) a 17.218(5) A, c 10.859(3) A, and V 2787.9 A3. The structure was solved by the Patterson method, and full-matrix least-squares refinement led to a final R value of 0.026. The crystal structure is characterized by parallel infinite spiral chains built up of molecules connected by Sn … S intermolecular contacts of 3.31 A. The molecules exhibit a strongly distorted ψ-trigonal bipyramidal geometry around the tin atom with the phosphorus atom in an equatorial position and an SnP distance of 2.61 A The eight-membered ring adopts a boat—boat conformation. The reaction of compound 1 with Cr(CO)6 in THF under UV irradiation yields the corresponding chromium pentacarbonyl complex.

Reactions of phenylbis(trimethylsilyl)arsine with pivaloyl imidechlorides yield iminoacylsilylarsines, which rearrange to the N -silylated As C -isomers according to a temperature dependent equilibrium. Spectroscopic data are given.

The synthesis of Me 2 Sn(CH 2 CH 2 CH 2 ) 2 NMe and MeSn(CH 2 CH 2 CH 2 ) 3 N is reported. The transannular SnN interaction is confirmed by 1 H, 13 C and 119 Sn NMR spectroscopy.

The reaction of the functional Grignard reagent [CH2N(Me)CH2CH2CH2MgCl]2, prepared from N,N′-dimethyl-N,N′-bis(3-chloropropyl)ethylene diamine and magnesium, with tin tetrachloride followed by derivatisations leads to new tin heterocycles of the general type RR′Sn[CH2CH2CH2N(Me)CH2]2 (4–10, R = R′ = Cl, Br, I, OMe, SPh, Me, Ph; 11, R = Me, R′ = Cl; 12, R = Me, R′ = Br; 13, R = Me, R′ = I). In 4–8 the tin atoms have octahedral configurations with the carbon atoms attached to tin trans to each other. The tetraorganotin compounds 9 and 10 show no transannular SnN interactions. The nonsymmetrically substituted triorganotin compounds 11–13 exhibit ionic pentavalent structures. Their intramolecular mobility with ΔG*Tc values of 40.1 to 42.6 kJ/mol can be interpreted in terms of a partial Berry process. For the purpose of comparison, compounds of the type [CH2N(Me)CH2CH2CH2SnMe2R]2 (14, R = Me; 15, R = Cl) have been prepared and studied analogously.

Summary The 1 H-NMR-spectra of the N -alkyl-5,5-di-t-butyldiptychoxazstannolidines at various temperatures are reported. The parameters of activation are calculated by means of the coalescence of both t-butyl signals. A mechanism of dissociation—inversion is discussed. The dependence of the 119 Sn C CH coupling constants as well as the parameters of activation on the donor strength of the solvents indicates the presence of hexacoordinated species.

The synthesis of Me2Si(CH2CH2CH2)2NMe and RSi(CH2CH2CH2)3N (R = Cl, Me) is reported. Their structure is investigated by means of 1H, 13C and 29Si NMR spectroscopy and mass spectrometry.

By addition of phenylarsino-acetic acid and β-n-butylarsino- and β-phenylarsino-propionic acid, respectively, to aldehydes and ketones, followed by an intramolecular condensation reaction, 1.3-oxarsolan-5-ones and 1,3-oxarsenan-6-ones, respectively, are formed. The structures of the compounds are established by investigating their IR, 1H NMR and mass spectra.

1-Aza-5-stanna-5-chlorotricyclo[3.3.3.0]undecane crystallizes in the space group P 6 3 . The unit cell, with a 8.435(3), c 9.243(2) A, V 569.5(3) A 3 , contains two molecules. The structure was refined to a final R value of 0.057. The molecules CISn(CH 2 CH 2 CH 2 ) 3 N belong to the point group 3, and the Sn, Cl and N atoms lie on the crystallographic 3-axis. The tin atom has a trigonal bipyramidal environment with the nitrogen and chlorine atoms in apical positions. The tin-nitrogen intramolecular interaction is 2.372(29) A.

The crystal and molecular structure of CH 2 [(C 6 H 5 )Sn(SCH 2 CH 2 ) 2 NCH 3 ] 2 were determined by X-ray diffraction. Both tin atoms show approximate trigonal-bipyramidal coordination, but the two phenyl rings and the methylene bridge do not occupy the same sites around the two metal centers. The 1 H, 13 C, 119 Sn data at various temperatures and magnetic fields indicate the presence in the slow exchange region of three isomers. The observations are interpreted on the basis of the assumption that in solution the phenyl groups can occupy both equatorial positions, both axial positions or one axial and one equatorial position. The last combination which is observed in the solid state, corresponds to the major isomer in solution. The stereochemical correspondence between this system and six-coordinate cis -bis-chelate complexes of the type M(AB) 2 X 2 is outlined. In the fast exchange region the spectra show that only one residual isomer is present. These observations imply that in the main isomerization process the tin atoms rearrange independently of each other. The data indicate that this rearrangement proceeds through the dissociation-inversion mechanism previously discussed.

Reactions of o-Lithio-lithiumphenolate and o-Lithio-N-methyl-lithiumanilide with Halides of Phosphorus, Arsenic and Silicon The title compounds and chlorides of the type CIERn (E = P, As, Si) react smoothly in a molecular ratio of 1:2 to give the corresponding disubstituted phenole and N-methylaniline derivatives, respectively. Attempts with an 1:1 ratio show different results depending on the reactivity of the EO or EN species towards organolithium reagents.

The selective cleavage of phenylsilanes by triflic acid gives novel silyltriflates. Unique, substituted derivatives have been synthesized by alkylation with organometallic reagents. Triflate derivatives of oligo- and cyclo-silanes are similarly formed.

The reaction of dialkyltin oxides or dialkyltin dialkoxides with N-methyliminodiacetic acid in dimethylformamide/toluene gives the title compounds in 80–90% yields. The structure of these compounds was investigated by NMR, IR and mass spectroscopy. The temperature dependent 1H and 13C NMR spectra are interpreted by a dissociation—inversion mechanism.

1-Methyl-1,3-benzazaphospholes are described; the 2H derivate and t-BuLi give the title compound, characterized by reaction with CO 2 and Me 3 SiCl; NMR data confirm the results.

The preparation of ω-phosphinoalkyldiorganostannanes R 2 Sn(H)(CH 2 n -P(H)R′ (R = Et, Bu; R′ = H, Ph; n = 2, 3) is reported. The oxidation of these compounds with sulfur or H 2 O 2 leads to the 1,2,3-stannathia- and 1,2,3-stannaoxaphospholane- and -phosphorinane ring systems, respectively. The metalation of the title compounds takes place primarily at the SnH-bond. Azobenzene cyclizes 3-phenylphosphinopropyldiorganostannanes to 1,2-stannaphospholanes. The new compounds were identified by analytical and spectroscopic (NMR, IR) methods.

Sodium phenylarside and sodium-n-butylarside react with chloro (bromo) carboxylic acids and their sodium salts, amides or esters in liquid ammonia to give the corresponding secondary arsino carboxylic acid derivatives. Their properties and reactions are described. In some cases the derivatives of arsindiyl-di-carboxylic acids are obtained as by-products due to transmetalation reactions.

(Dialkylaminomethyl)chlorosilanes have been obtained by the reaction of trichlorosilane with bis(dimethylamino)methane. The corresponding stannanes have been prepared by the addition of methyleneimmonium halides to SnCl2. In the silicon compounds a covalent SiCH2N bond is observed, while the tin compounds have ionic structures. Reactions of the new compounds are described.

Zusammenfassung The reaction of o -(diphenylphosphine)phenylbromomagnesium with tin(II) chloride leads to the formation of a tin(II)-Tin(IV) containing compound, while treatment of Cl 2 SnW(CO) 5 with o -(diphenylphosphine)phenyllithium yields a phosphino-stabilized stannylene complex. The compounds were characterized by 13 C, 31 P, 119 Sn NMR and Mossbauer spectroscopy.