Monocarbaborane anion chemistry. The elusive C-arylated [PhCB11H11]-, [PhCB9H9]- and [PhCB8H8]- anions

B10H14 and PhCHO yield [6-Ph-nido-6-CB9H11]- (94%), from which the nine-vertex C-phenyl monocarbaborane anion [4-Ph-closo-4-CB8H8]- (68%) can be obtained by heating at 200 degrees C, and from which the twelve- and ten-vertex analogues [1-Ph-closo-1-CB11H11]- (50%) and [4-Ph-closo-4-CB9H9]- (25%) can be obtained by heating at 210 degrees C with BH3(NEt3).     

Polyhedral monocarbaborane chemistry. Some C-phenylated seven, eight, nine, ten, eleven and twelve-vertex species

Some synthetic and structural systematics for monocarbaboranes, using the C-phenylated motif as the example, are investigated. The 10-vertex [6-Ph-nido-6-CB(9)H(11)](-) anion 1, from reaction of PhCHO with B(10)H(14) in KOH/H(2)O, is a useful entry synthon into C-phenyl monocarbaborane chemistry. Treatment of anion 1 with Na/thf yields the 10-vertex [1-Ph-closo-1-CB(9)H(9)](-) anion 2a, whereas treatment of anion 1 with iodine in alkaline solution yields the isomeric 10-vertex [2-Ph-closo-2-CB(9)H(9)](-) anion 2b, which isomerises quantitatively to 2a on heating under reflux in DME. Thermolysis of anion 1 yields the 9-vertex [4-Ph-closo-4-CB(8)H(8)](-) anion 5, whereas treatment of anion 1 with FeCl(3)/HCl gives neutral 9-vertex [4-Ph-arachno-4-CB(8)H(13)] 3. Compound 3 gives neutral 9-vertex [1-Ph-nido-1-CB(8)H(11)] 4 in refluxing toluene, and gives the 7-vertex [2-Ph-closo-2-CB(6)H(6)](-) anion 7 and the 8-vertex [1-Ph-closo-1-CB(7)H(7)](-) anion 6 in refluxing toluene with NEt(3). Reaction of 1 with [BH(3)(thf)] yields the 11-vertex [7-Ph-nido-7-CB(10)H(12)](-) anion 8 which can be converted to the 12-vertex [1-Ph-closo-1-CB(11)H(11)](-) anion 10 using [BH(3)(SMe(2))]; alternatively, anion 1 yields anion 10 directly on treatment with [BH(3)(NEt(3))]. Treatment of anion 8 with I(2)/KOH yields the 11-vertex [2-Ph-closo-2-CB(10)H(10)](-) anion 9. The structures of anions 1, 2a, 2b, 5, 6, 7, 8, 9 and 10 have been established by single-crystal X-ray diffraction analyses of their [NEt(4)](+) salts, and those of neutral 3 and 4 estimated by DFT calculations at the B3LYP/6-31G* level; similar calculations have also been applied to the new anionic closo species 2a, 2b, 5, 6, 7, 9 and 10. Crystals of the [NEt(4)](+) salt of the [2-Ph-closo-2-CB(6)H(6)](-) anion 7 required synchrotron X-radiation for sufficient diffraction intensity for molecular-structure elucidation. The syntheses are in principle generally applicable to give extensive derivative C-aryl and C-alkyl chemistries.     

Monocarbaborane anion chemistry. [COOH], [CH2OH] and [CHO] units as functional groups on ten-vertex monocarbaborane anionic compounds

B(10)H(14) reacts with para-C(6)H(4)(CHO)(COOH) in aqueous KOH solution to give the [nido-6-CB(9)H(11)-6-(C(6)H(4)-para-COOH)](-) anion 1, which undergoes cage closure with iodine in alkaline solution to give the [closo-2-CB(9)H(9)-2-(C(6)H(4)-para-COOH)](-) anion 2. Upon heating, anion 2 rearranges to form the [closo-1-CB(9)H(9)-1-(C(6)H(4)-para-COOH)](-) anion 3. Similarly, B(10)H(14) with glyoxylic acid OHCCOOH in aqueous KOH gives the [arachno-6-CB(9)H(13)-6-(COOH)](-) anion 4, which undergoes cage closure with iodine in alkaline solution to give the [closo-2-CB(9)H(9)-2-(COOH)](-) anion 5. Upon heating, anion 5 rearranges to give the [closo-1-CB(9)H(9)-1-(COOH)](-) anion 6. Reduction of the [COOH] anions 3 and 6 with diisobutylaluminium hydride gives the [CH(2)OH] hydroxy anions [closo-1-CB(9)H(9)-1-(C(6)H(4)-para-CH(2)OH)](-) and [closo-1-CB(9)H(9)-1-(CH(2)OH)](-) 8 respectively. The [closo-1-CB(9)H(9)-1-(C(6)H(4)-para-CH(2)OH)](-) anion 7 can also be made via isomerisation of the [closo-2-CB(9)H(9)-2-(C(6)H(4)-para-CH(2)OH)](-) anion 9, in turn obtained from the [nido-6-CB(9)H(11)-6-(C(6)H(4)-para-CH(2)OH)](-) anion 10, which is obtained from the reaction of B(10)H(14) with terephthaldicarboxaldehyde, C(6)H(4)-para-(CHO)(2), in aqueous KOH solution. Oxidation of the hydroxy anions 7 and 8 with pyridinium dichromate gives the aldehydic [closo-1-CB(9)H(9)-1-(C(6)H(4)-para-CHO)](-) anion 11 and the aldehydic [closo-1-CB(9)H(9)-1-(CHO)](-) anion 12 respectively, characterised as their 2,4-dinitrophenylhydrazone derivatives, the [closo-1-CB(9)H(9)-1-C(6)H(4)-para-CH=N-NHC(6)H(3)(NO(2))(2)](-) anion 13 and the [closo-1-CB(9)H(9)-1-CH=N-NHC(6)H(3)(NO(2))(2)](-) anion respectively.     

Unusual interaction of alkynes with nine-vertex arachno-monocarbaboranes 4-CB8H14 and [4-CB8H13]-

Alkynes R(1)R(2)C(2) react with the neutral monocarbaborane arachno-4-CB(8)H(14) (1) at elevated temperatures (115-120 degrees C) under the formation of the derivatives of the ten-vertex dicarbaborane nido-5,6-C(2)B(8)H(12) (2) of general formula 9-Me-5,6-R1,R2-nido-5,6-C(2)B(8)H(9) (where R1,R2 = H,H 2a; Me,Me 2b; Et,Et 2c, H,Ph 2d, and Ph,Ph 2e) in moderate yields (26-52%). Side reaction with PhC(2)H also yields 1-Ph-6-Me-closo-1,2-C(2)B(8)H(8) (3d). In contrast, the reaction between [arachno-4-CB(8)H(13)](-) anion ((-)) and PhC(2)H produces a mixture of the closo anions [1-CB7H8]- (4-) and [1-CB6H7]- (5-) (yields 32 and 24%, respectively). Individual compounds were isolated and purified by liquid chromatography and characterized by NMR spectroscopy ((11)B, (1)H and (13)C) combined with two-dimensional [(11)B-(11)B]-COSY and (1)H-{(11)B(selective)}NMR techniques.     

Diazotization of the amino acid [closo-1-CB9H8-1-COOH-6-NH3] and reactivity of the [closo-1-CB9H8-1-COO-6-N2]- anion

A comparative study of the reactivity of dinitrogen acids [closo-1-CB(9)H(8)-1-COOH-10-N(2)] (3[10]) and [closo-1-CB(9)H(8)-1-COOH-6-N(2)] (3[6]) was conducted by diazotization of a mixture of amino acids [closo-1-CB(9)H(8)-1-COOH-6-NH(3)] (1[6]) and [closo-1-CB(9)H(8)-1-COOH-10-NH(3)] (1[10]) with NO(+)BF(4)(-) in the presence of a heterocyclic base (pyridine, 4-methoxypyridine, 2-picoline, or quinoline). The 10-amino acid 1[10] formed an isolable stable 10-dinitrogen acid 3[10], while the 6-dinitrogen carboxylate 3[6](-) reacted in situ, giving products of N-substitution at the B6 position with the heterocyclic solvent (4[6]). The molecular and crystal structures for pyridinium acid 4[6]a were determined by X-ray crystallography. The electronic structures and reactivity of the 6-dinitrogen derivatives of the {1-CB(9)} cluster were assessed computationally at the B3LYP/6-31G(d,p) and MP2/6-31G(d,p) levels of theory and compared to those of the 10-dinitrogen, 2-dinitrogen, and 1-dinitrogen analogues.     

Homodinuclear iron thiolate nitrosyl compounds [(ON)Fe(S,S-C6H4)2 Fe(NO)2]- and [(ON)Fe(SO2,S-C6H4)(S,S-C6H4)Fe(NO)2]- with {Fe(NO)}7-{Fe(NO)2}9 electronic coupling: new members of a class of dinitrosyl iron complexes

Reaction of Fe(CO)2(NO)2 and [(ON)Fe(S,S-C6H3R)2]- (R = H (1), CH3 (1-Me))/[(ON)Fe(SO2,S-C6H4)(S,S-C6H4)]- (4) in THF afforded the diiron thiolate/sulfinate nitrosyl complexes [(ON)Fe(S,S-C6H3R)2 Fe(NO)2]- (R = H (2), CH3 (2-Me)) and [(ON)Fe(S,SO2-C6H4)(S,S-C6H4)Fe(NO)2]- (3), respectively. The average N-O bond lengths ([Fe(NO)2] unit) of 1.167(3) and 1.162(4) A in complexes 2 and 3 are consistent with the average N-O bond length of 1.165 A observed in the other structurally characterized dinitrosyl iron complexes with an {Fe(NO)2}9 core. The lower nu(15NO) value (1682 cm(-1) (KBr)) of the [(15NO)FeS4] fragment of [(15NO)Fe(S,S-C6H3CH3)2 Fe(NO)2]- (2-Me-15N), compared to that of [(15NO)Fe(S,S-C6H3CH3)2]- (1-Me-15N) (1727 cm(-1) (KBr)), implicates the electron transfer from {Fe(NO)2}10 Fe(CO)2(NO)2 to complex 1-Me/1 may occur in the process of formation of complex 2-Me/2. Then, the electronic structures of the [(NO)FeS4] and [S2Fe(NO)2] cores of complexes 2, 2-Me, and 3 were best assigned according to the Feltham-Enemark notation as the {Fe(NO)}7-{Fe(NO)2}9 coupling (antiferromagnetic interaction with a J value of -182 cm(-1) for complex 2) to account for the absence of paramagnetism (SQUID) and the EPR signal. On the basis of Fe-N(O) and N-O bond distances, the dinitrosyliron {L2Fe(NO)2} derivatives having an Fe-N(O) distance of approximately 1.670 A and a N-O distance of approximately 1.165 A are best assigned as {Fe(NO)2}9 electronic structures, whereas the Fe-N(O) distance of approximately 1.650 A and N-O distance of approximately 1.190 A probably imply an {Fe(NO)2}10 electronic structure.     

Monocarbaborane chemistry. Preparation and characterisation of [4-CB8H9]-, the 'missing' closo-carbaborane anion

Thermolysis in the solid state of Cs+[arachno-CB9H14]-, or of Cs+[nido-CB9H12]-, or the oxidation of nido-1-CB8H12 with I2 in THF at -78 degrees C in the presence of NEt3, gives the first nine-vertex closo monocarbaborane, the stable [closo-4-CB8H9]- anion, in yields of 56, 61 and 75%, respectively.     

Borane reaction chemistry. Alkyne insertion reactions into boron-containing clusters. Products from the thermolysis of [6,9-(2-HC[triple bond]C-C5H4N)2-arachno-B10H12

The stirring of [ortho-(HC[triple bond]C)-C(5)H(4)N] with [nido-B(10)H(14)] in benzene affords [6,9-{ortho-(HC[triple bond]C)-C(5)H(4)N}(2)-arachno-B(10)H(12)] 1 in 93% yield. In the solid state, 1 has an extended complex three-dimensional structure involving intramolecular dihydrogen bonding, which accounts for its low solubility. Thermolysis of 1 gives the known [1-(ortho-C(5)H(4)N)-1,2-closo-C(2)B(10)H(11)] 2 (13%), together with new [micro-5(N),6(C)-(NC(5)H(4)-ortho-CH(2))-nido-6-CB(9)H(10)] 3 (0.4%), [micro-7(C),8(N)-(NC(5)H(4)-ortho-CH(2))-nido-7-CB(10)H(11)] (0.4%) , 4 binuclear [endo-6'-(closo-1,2-C(2)B(10)H(10))-micro-(1(C),exo-6'(N))-(ortho-C(5)H(4)N)-micro-(exo-8'(C),exo-9'(N))-(ortho-(CH(2)CH(2))-C(5)H(4)N)-arachno-B(10)H(10)] (0.5%) 5, and [exo-6(C)-endo-6(N)-(ortho-(CH[double bond]CH)-C(5)H(4)N)-exo-9(N)-(ortho-(HC[triple bond]C)-C(5)H(4)N)-arachno-B(10)H(11)] 6. An improved solvent-free route to 2 is also presented. This set of compounds features an increasing cluster incorporation of the ethynyl moiety, initially by an effective internal hydroboration, affording an arachno to nido and then a nido to arachno:closo sequence of cluster geometry. An alternative low-temperature route to internal hydroboration is demonstrated in the room temperature reaction of [closo-B(11)H(11)][N(n)Bu(4)](2) with CF(3)COOH and [ortho-(HC[triple bond]C)-C(5)H(4)N], which gives [micro-1(C),2(B)-[ortho-C(5)H(4)N-CH(2)]-closo-1-CB(11)H(10)] 7 (40%) in which one carbon atom is incorporated into the cluster; a similar reaction with [ortho-(N[triple bond]C)-C(5)H(4)N] affords [N(n)Bu(4)][7-(ortho-N[triple bond]C-C(5)H(4)N)-nido-B(11)H(12)], 8 (68%) and stirring [ortho-(N[triple bond]C)-C(5)H(4)N] with [nido-B(10)H(14)] quantitatively affords the cyano analogue of 1, [6,9-{ortho-(N[triple bond]C)-C(5)H(4)N}(2)-arachno-B(10)H(12)] 9. All compounds were characterised by single-crystal X-ray diffraction analysis and NMR spectroscopy.     

[C6N2H18]2[Mo5O15(HPO4)2]·H2O的水热合成与结构表征

通过水热法合成了一个新化合物[C6N2H18]2[Mo5O15(HPO4)2]·H2O,并通过IR光谱、ICP、元素分析、差热与热重分析和X射线单晶衍射分析等手段进行了表征.结果表明,晶体属三方晶系,P3(2)21空间群,a=1.1231(1)nm,c=2.2802(5)nm,V=2.4911(7)nm3,Dx=2.835Mg/m3,Z=6,最后的一致性因子R=0.0227,wR=0.0675.阴离子中Mo5O15构成一环状结构,2个HPO4一个连在环的下方,一个连在环的上方,形成类似于“飞碟”状的结构,阳离子为2个质子化的四甲基乙二胺.     

A practical synthesis of isomerically pure 1,10-difunctionalized derivatives of the [closo-1-CB9H10] anion

The isomer-free [closo-1-CB9H(8)-1-COOH-10-I]- anion was prepared in four steps and 10% overall yield from B10H14. The key step is the skeletal isomerization of the [closo-2-CB9H8-2-COOH-7-I]- anion to a mixture of the 10- and 6-iodo derivatives of [closo-1-CB9H(9)-1-COOH]- formed in up to a 3:1 ratio. The carboxylic acid 4 was converted to the amine [closo-1-CB9H(8)-1-NH(2)-10-I]- using the Curtius reaction. The relative thermodynamic stability of each product was calculated at the DFT and MP2 levels of theory. The regioselectivity of electrophilic substitution in [closo-CB9H10]- derivatives was briefly investigated using the NBO population analysis of the MP2 wave function.     

Reductive degradation of nido-1-CB8H12 into smaller-cage carborane systems via new monocarbaboranes [arachno-5-CB8H13](-) and closo-2-CB6H8

Treatment of the nido-1-CB8H12 (1) carborane with NaBH4 in THF at ambient temperature led to the isolation of the stable [arachno-5-CB8H13]- (2(-)), which was isolated as Na+[5-CB8H13]-.1.5 THF and PPh4 +[5-CB8H13]- in almost quantitative yield. Compound 2(-) underwent a boron-degradation reaction with concentrated hydrochloric acid to afford the arachno-4-CB7H13 (3) carborane in 70 % yield, whereas reaction between 2(-) and excess phenyl acetylene in refluxing THF gave the [closo-2-CB6H7]- (4-) in 66 % yield. Protonation of the Cs+4(-) salt with concentrated H2SO4 or CF3COOH in CH2Cl2 afforded a new, highly volatile 2-CB6H8 (4) carborane in 95 % yield, the deprotonation of which with Et3N in CH2Cl2 leads quantitatively to Et3NH+[2-CB6H7](-) (Et3NH+4(-)). Both compounds 4- and 4 can be deboronated through treatment with concentrated hydrochloric acid in CH2Cl2 to yield the carbahexaborane nido-2-CB5H9 (5) in 60 % yield. New compounds 2-, 3, and 4 were structurally characterised by the ab initio/GIAO/MP2/NMR method. The method gave superior results to those carried out using GIAO-HF when relating the calculated 11B NMR chemical shifts to experimental data.     

The synthesis and characterization of compounds of the type Hg[1-C(6)H(4)-2-C(H)=NC(6)H(5-n)R(n)](2)

The organomercurial compounds Hg[1-C(6)H(4)-2-C(H)=NC(6)H(5-n)R(n)](2) (R = 4-NMe(2), 6a; 4-Me, 6b; 4-I, 6c; 4-NO(2), 6d; 2-(i)Pr, 6e; 2-Me, 6f; 2,6-(i)Pr(2), 6g; 2,6-Me(2), 6h) have been prepared in good overall yield from 2-bromobenzaldehyde. All of the compounds have been characterized by elemental analysis, (1)H NMR, (13)C[(1)H] NMR, and infrared spectroscopy. In addition, compounds 6a [C(30)H(30)HgN(4), triclinic, P, a = 6.20000(10) A, b = 9.2315(2) A, c = 10.9069(3) A, alpha = 85.8510(10) degrees, beta = 89.3570(10) degrees, gamma = 87.206(2) degrees, Z = 1], 6b [C(28)H(24)HgN(2), monoclinic, P2(1)/c, a = 12.8260(5) A, b = 14.0675(4) A, c = 6.1032(2) A, beta = 90.0990(10) degrees, Z = 2], 6g [C(38)H(44)HgN(2), triclinic, P, a = 8.2626(2) A, b = 9.8317(2) A, c = 11.8873(3) A, alpha = 103.6650(10) degrees, beta = 109.3350(10) degrees, gamma = 104.627(2) degrees, Z = 1], and 6h [C(30)H(28)HgN(2), monoclinic, P2(1)/c, a = 12.5307(2) A, b = 10.9852(2) A, c = 18.2112(2) A, beta = 104.0190(10) degrees, gamma = 87.206(2) degrees, Z = 4] have been characterized by low-temperature single-crystal X-ray diffraction studies, and two different molecular geometries about the central mercury atom have been observed; intramolecular contacts suggest a van der Waals radius for Hg of 2.1-2.2 A.     

Organoiron compounds derived from the indium 'carbene analogues', [In(N(Ar)C(Me))2CH] (Ar = dipp = 2,6-iPr2C6H3; = Mes = 2,4,6-Me3C6H2)

Oxidative insertion of the In(I) 'carbene analogues', [In{N(Dipp)C(Me))2CH] (Ar = Dipp = 2,6-iPr2C6H3; Ar = Mes = 2,4,6-Me3C6H2) into the Fe-I bond of [CpFe(CO)2I] occurred cleanly and under mild conditions to yield the In(III) compounds [CH((CH3)2CN-2,6-iPr2C6H3)2In(I)FeCp(CO)2] and [CH( (CH3)2CN-2,4,6-Me3C6H3)2In(I)FeCp(CO)2], which have been fully characterised in solution and the solid state. Attempts to abstract the iodide anion from [CH( (CH3)2CN-2,6-iPr2C6H3)2In(I)FeCp(CO)2] to form cationic species containing a coordinated indium diyl were unsuccessful and resulted in a complex mixture of products from which two ionic species were isolated. Neither cation was found to contain indium by X-ray crystallographic analysis. These observations were indicative of ill-defined decomposition pathways as have been noted by previous workers. A further attempt to form a cationic iron species containing a coordinated [In(N(Dipp)C(Me) )2CH] fragment resulted in oxidation of the iron centre from Fe(II) to Fe(III), with deposition of indium metal, and the isolation of a cationic Fe(III) beta-diketiminate complex.     

CRYSTAL AND MOLECULAR STRUCTURE OF THE HEXANUCLE-AR DIAZENIDO-OXOMOLYBDATE [(n-C_4H_9)_4N]_3[Mo_6O_(18)-(N_2C_6H_3-2,4-(NO_2)_2]

<正> Crystal of the title complex [(n-C4H9)4N]3[Mo6O18(N2C6H3-2,4-(NO2)2](Mr= 1710. 5) is orthorhombic with space group P21cn (Pna21), a = 17. 304(3), b = 17.580(2), c=24. 355(4) (?), V = 7409(2)(?)3, Z = 4, Dc=1. 60g/ cm3, μ=10. 29cm-1, F (000) = 3647. The structural solutions and refinements based on 3900 reflections (I≥3σ(I)) converged at R = 0. 0575, Rw =0. 0498. The atoms of Mo(3), Mo(4), O(1), O(5), O(9), O(11) and the [N2C6H3-2,4-(NO2)2] unit in the complex anion locate approximately in a plane about which the complex anion is nearly symmetrical.     

Ten-vertex iron-monocarbollide complexes: synthesis and reactivity of the anion [4,9-{Fe(CO)4}-9,9,9-(CO)3-arachno-9,6-FeCB8H11]-

The reagent [arachno-4-CB8H14] reacts with [Fe3(CO)12] in tetrahydrofuran (THF) at reflux temperatures, followed by addition of [N(PPh3)2]Cl, to afford [N(PPh3)2][4,9-{Fe(CO)4}-9,9,9-(CO)3-arachno-9,6-FeCB8H11] (3). In the anion of 3, one iron atom is part of the open CBBFeBB face of a 10-vertex {arachno-9,6-FeCB8} cage, to which the second iron atom is attached via an Fe-Fe bond and an additional exo-polyhedral Fe-B sigma bond. Upon heating 3 in refluxing toluene, the closed 10-vertex species [N(PPh3)2][2,2,2-(CO)3-closo-2,1-FeCB8H9] (4) is obtained, whereas the isomeric compound [N(PPh3)2][6,6,6-(CO)3-closo-6,1-FeCB8H9] (5) is isolated upon heating [closo-4-CB8H9]- and [Fe3(CO)12] in refluxing THF with subsequent addition of [N(PPh3)2]Cl. Protonation of 3 using CF3SO3H in CH2Cl2 gives the charge-compensated compound [4,9-{Fe(CO)4}-4-(mu-H)-9,9,9-(CO)3-arachno-9,6-FeCB8H11] (6), in which the B-Fe sigma bond of the precursor has been converted to a B-H right harpoon-up Fe linkage. In contrast, 3 with {M(PPh3)}+ gives the trimetallic species [1,3,4,9-{MFe(CO)4(PPh3)}-1,3-(mu-H)2-9,9,9-(CO)3-arachno-9,6-FeCB8H9] (M = Cu (7), Ag 8) in which the three metal centers form a V-shaped M-Fe-Fe unit. Compound 6 reacts with PEt3 in the presence of Me(3)NO to yield [4,9-(PEt3)2-9,9-(CO)2-nido-9,6-FeCB8H10] (9). In the latter, the formerly exo-polyhedral {Fe(CO)4} fragment has been replaced by a PEt3 ligand, with a second PEt3 substituting one CO group at the remaining cluster iron vertex. The novel structural features of compounds 3-9 have been confirmed by single-crystal X-ray diffraction studies.     

Neodymium monochloride and monoallyl complexes {2-[Ph2P(O)]C6H4NC(But)N(2,6-Me2C6H3)}2NdR (R = Cl,CH2CH=CH2) with the tridentate amidinate ligand in the catalysis of ring-opening polymerization of cyclic esters

Russian Chemical Bulletin - The reaction of tridentate amidine 2-[Ph2P(O)]C6H4NHC(But)=N(2,6-Me2C6H3) (1) containing the side-chain donor group Ph2P=O with NdCl[N(SiMe3)2]2 (2) in a molar ratio...     

Influence of hydrogen bonding on the assembly of six-membered vanadium borophosphate cluster anions: synthesis and structures of (NH4)2(C2H10N2)6[Sr(H2O)5]2[V2P2BO12](6)10H2O, (NH4)2(C3H12N2)6[Sr(H2O)4]2[V2P2BO12](6)17H2O, and (NH4)3(C4H14N2)4 5[Sr(H2O)5]2[Sr(H2O)4][V2P2BO12]6 10H2O

Three new strontium vanadium borophosphate compounds, (NH4)2(C2H10N2)6[Sr(H2O)5]2[V2P2BO12]6 10H2O (Sr-VBPO1) (1), (NH4)2(C3H12N2)6[Sr(H2O)4]2[V2P2BO12]6 17H2O (Sr-VBPO2) (2), and (NH4)3(C4H14N2)4.5[Sr(H2O)5]2[Sr(H2O)4][V2P2BO12]6 10H2O (Sr-VBPO3) (3) have been synthesized by interdiffusion methods in the presence of diprotonated ethylenediamine, 1,3-diaminopropane, and 1,4-diaminobutane. Compound 1 has a chain structure, whereas 2 and 3 have layered structures with different arrangements of [(NH4) [symbol: see text] [V2P2BO12]6] cluster anions within the layers. Crystal data: (NH4)2(C2H10N2)6[Sr(H2O)5]2[V2P2BO12]6 10H2O, monoclinic, space group C2/c (no. 15), a = 21.552(1) A, b = 27.694(2) A, c = 20.552(1) A, beta = 113.650(1) degrees, Z = 4; (NH4)2(C3H12N2)6[Sr(H2O)4]2[V2P2BO12]6 17H2O, monoclinic, space group I2/m (no. 12), a = 15.7618(9) A, b = 16.4821(9) A, c = 21.112(1) A, beta = 107.473(1) degrees, Z = 2; (NH4)3(C4H14N2)4.5[Sr(H2O)5]2[Sr(H2O)4] [V2P2BO12]6 10H2O, monoclinic, space group C2/c (no. 15), a = 39.364(2) A, b = 14.0924(7) A, c = 25.342(1) A, beta = 121.259(1) degrees, Z = 4. The differences in the three structures arise from the different steric requirements of the amines that lead to different amine-cluster hydrogen bonds.     

Macropolyhedral boron-containing cluster chemistry. Cluster assembly about a molybdenum centre. Formation of the 19-vertex [(CO)2MoB16H15C2Ph2]- anion

Fusion of nine-vertex [1-Ph-nido-1-CB8H11] with [Mo(CH3CN)3(CO)3] in the presence of tetramethylnaphthalenediamine gives the nineteen-vertex macropolyhedral metallaborane anion [(CO)2MoB16H15C2Ph2]- with a molybdenum(VI) twelve-atom coordination sphere.     

Arylzinc alkoxides: [ArZnOCHPr(i)2]2 and Ar2Zn3(OCHPr(i)2)4 when Ar = C6H5, p-CF3C6H4, 2,4,6-Me3C6H2, and C6F5

From the reactions between diarylzinc compounds (Ar2Zn) and the alcohol (Pr(i)2CHOH) in toluene, the compounds [ArZn(OCHPr(i)2)]2 (Ar = C6H5, C6F5, p-CF3C6H4, and 2,4,6-Me3C6H2) have been isolated and shown to exist in equilibra with the trinuclear complexes Ar2Zn3(OCHPr(i)2)4 and Ar2Zn when Ar = C6H5, C6F5, and p-CF3C6H4. The trinuclear complexes have also been prepared from reactions of the Ar2Zn compounds with the alcohol, which reveals that the ease of Zn-C(aryl) bond cleavage is sensitive to the nature of the Ar group: C6H5 > 4-CF3C6H4 > C6F5. The molecular structures of Ar2Zn3(OCHPr(i)2)4 where Ar = p-CF3C6H4 and C6F5 and [ArZn(OCHPr(i)2)]2 where Ar = C6F5, p-CF3C6H4, and 2,4,6-Me3C6H2 are reported based on single-crystal X-ray diffraction studies. The X-ray structure of Zn(p-CF3C6H4)2 is also reported. The reactivity of these new compounds toward the polymerization of propylene oxide (PO) and the copolymerization of PO and CO2 have been investigated along with related reactions involving the partial hydrolysis of the Ar2Zn and R2Zn compounds, where R = t-Bu, n-Bu, and n-Oct. These results are compared with the previous studies employing Et2Zn as an organozinc precursor.     

Synthesis, structural characterization, reactivity, and thermal stability of [eta(5):sigma-Me2C(C5H4)(C2B10H10)]Ti(R)(NMe2)

Reaction of [eta:(5)sigma-Me2C(C5H4)(C2B10H10)]TiCl(NMe2) (1) with 1 equiv of PhCH2K, MeMgBr, or Me3SiCH2Li gave corresponding organotitanium alkyl complexes [eta:(5)sigma-Me2C(C5H4)(C2B10H10)]Ti(R)(NMe2) (R = CH2Ph (2), CH2SiMe3 (4), or Me (5)) in good yields. Treatment of 1 with 1 equiv of n-BuLi afforded the decomposition product {[eta:(5)sigma-Me2C(C5H4)(C2B10H10)]Ti}2(mu-NMe)(mu:sigma-CH2NMe) (3). Complex 5 slowly decomposed to generate a mixed-valence dinuclear species {[eta:(5)sigma-Me2C(C5H4)(C2B10H10)]Ti}2(mu-NMe2)(mu:sigma-CH2NMe) (6). Complex 1 reacted with 1 equiv of PhNCO or 2,6-Me2C6H3NC to afford the corresponding monoinsertion product [eta:(5)sigma-Me2C(C5H4)(C2B10H10)]Ti(Cl)[eta(2)-OC(NMe2)NPh] (7) or [eta:(5)sigma-Me2C(C5H4)(C2B10H10)]Ti(Cl)[eta(2)-C(NMe2)=N(2,6-Me2C6H3)] (8). Reaction of 4 or 5 with 1 equiv of R'NC gave the titanium eta(2)-iminoacyl complexes [eta:(5)sigma-Me2C(C5H4)(C2B10H10)]Ti(NMe2)[eta(2)-C(R)=N(R')] (R = CH2SiMe3, R' = 2,6-Me2C6H3 (9) or tBu (10); R = Me, R' = 2,6-Me2C6H3 (11) or tBu (12)). The results indicated that the unsaturated molecules inserted into the Ti-N bond only in the absence of the Ti-C(alkyl) bond and that the Ti-C(cage) bond remained intact. All complexes were fully characterized by various spectroscopic techniques and elemental analyses. Molecular structures of 2, 3, 6-8, and 10-12 were further confirmed by single-crystal X-ray analyses.