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This study reports on the exploration of the phosphinoboration reaction with several thiosemicarbazones ([R.sup.5][R.sup.4]NC(S)N[R.sup.3]N=C[R.sup.1][R.sup.2]). Reactions between either [Ph.sub.2]PBpin (pin =1,2-[O.sup.2][C.sup.2][Me.sup.4]) or [Ph.sup.2]PBcat (cat =1,2-[O.sup.2][C.sup.6][H.sup.4]) with thiosemi-carbazones containing a terminal primary or secondary amine afforded boron-containing heterocyclic 1,3,4-thiadiazoline products in excellent yield. The addition of [Ph.sub.2]PBpin to thiosemicarbazones containing an [NMe.sub.2] group in the terminal position generated novel five-membered heterocycles in moderate yield, which included boron, sulfur, and nitrogen atoms. Heterocy-clization of the thiosemicarbazones occurs preferentially in the presence of functional groups such as acetyl and pyridyl groups. Key words: boron, borylation, phosphinoboration, 1,3,4-thiadiazoline, thiosemicarbazone, Introduction Historically, the reactivity of B--E-containing reagents has concentrated on hydroboration (E = H), (1-4) diboration (E = B), (5-7) and silylboration (E = Si (8-10) reactions, while the chemistry [...]

The well-known frameworks of the type M2(dobdc) (dobdc(4-) = 2,5-dioxido-1,4-benzenedicarboxylate) have numerous potential applications in gas storage and separations, owing to their exceptionally high concentration of coordinatively unsaturated metal surface sites, which can interact strongly with small gas molecules such as H2. Employing a related meta-functionalized linker that is readily obtained from resorcinol, we now report a family of structural isomers of this framework, M2(m-dobdc) (M = Mg, Mn, Fe, Co, Ni; m-dobdc(4-) = 4,6-dioxido-1,3-benzenedicarboxylate), featuring exposed M(2+) cation sites with a higher apparent charge density. The regioisomeric linker alters the symmetry of the ligand field at the metal sites, leading to increases of 0.4-1.5 kJ/mol in the H2 binding enthalpies relative to M2(dobdc). A variety of techniques, including powder X-ray and neutron diffraction, inelastic neutron scattering, infrared spectroscopy, and first-principles electronic structure calculations, are applied in elucidating how these subtle structural and electronic differences give rise to such increases. Importantly, similar enhancements can be anticipated for the gas storage and separation properties of this new family of robust and potentially inexpensive metal-organic frameworks.

Ten lipophilic amines were prepared from the reductive amination of vanillin and the corresponding primary amines using sodium borohydride in methanol. All compounds have been obtained elementally pure and an X-ray diffraction study on the 4-n-butylaniline derivative has confirmed the molecular structure. Whilst the overall antibiotic activity of the derivatives was low, some of these compounds, particularly the boronate ester 2-methoxy-4-((2-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenylamino)methyl)phenol (7), showed a promising degree of antimycobacterial activity against Mycobacterium tuberculosis H37Ra, where activity seemed to vary by the position of the boron substitution on the aniline ring. Key words: aliphatic amines, antimicrobial, antimycobacterial, boronate esters, lipophilic, tuberculosis. Nous avons prepare dix amines lipophiles par amination reductrice de la vanilline avec les amines primaires correspondantes a l'aide du borohydrate de sodium dans le methanol. La purete des composes obtenus a ete verifiee par analyse elementaire, et une etude par diffraction des rayons X du derive 4-n-butylaniline a permis de confirmer la structure moleculaire. Bien que l'activite antibiotique des derives ait ete faible, certains de ces composes, en particulier l'ester boronique 2-methoxy-4-([2-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenylamino]methyl)phenol (7), a fait preuve, dans une mesure prometteuse, d'une activite antimycobacterienne contre Mycobacterium tuberculosis H37Ra, ou l'activite semblait varier selon la position du substituant de bore sur le noyau aniline. [Traduit par la Redaction] Mots-cles: amines aliphatiques, agent antimicrobien, agent antimycobacterien, esters boroniques, lipophile, tuberculose., Introduction Although organoboron compounds, particularly boronic acids [RB[(OH).sub.2]] and boronate esters [RB[(OR').sub.2]], are ubiquitous in organic synthesis, (1,2) recent research has also found that these same small molecules can display [...]

Eight lipophilic 3-hydroxy-4-pyridinones have been prepared from a microwave-mediated reaction along with the corresponding copper(II) complexes. All complexes have been obtained elementally pure and X-ray diffraction studies on two of the copper complexes have confirmed the structure of these compounds. Some of these complexes showed a promising degree of anti-mycobacterial activity against Mycobacterium tuberculosis, where activity seemed to vary by substitution at the pyridinone nitrogen atom. Key words: aliphatic amines, anti-mycobacterial, copper, hydroxypyridinones, lipophilic, tuberculosis. Huit 3-hydroxy-4-pyridinones lipophiles et leurs complexes du cuivre(II) correspondants ont ete synthetises lors d'une reaction provoquee par des micro-ondes. Tous les complexes ont ete obtenus sous leur forme pure et des analyses diffractometriques aux rayons X des deux complexes du cuivre ont confirme la structure de ces composes. Certains de ces complexes ont presente un niveau prometteur d'activite antimycobacterienne contre Mycobacterium tuberculosis, cette activite semblant varier par substitution au niveau de l'atome d'azote de la pyridinone. [Traduit par la Redaction] Mots-cles: amines aliphatiques, antimycobacterien, cuivre, hydroxypyridinones, lipophile, tuberculose., Introduction All but forgotten in some societies, tuberculosis remains a serious infectious disease and is the leading cause of death in most of the developing countries around the world. Indeed, [...]

Classical Lewis acid-base adducts has provided access to the unique reactivity of frustrated Lewis pairs. This is shown with a mixture of 2,6-lutidine and B[([C.sub.6][F.sub.5]).sub.3] where an equilibrium has afforded the adduct and has also affected the heterolytic activation of [H.sub.2] and the ring opening of THF.

Static solid-state [super 35]Cl NMR spectra of the organometallic compounds are acquired with the quandrupolar Carr-Purcell Meiboom-Gill (QCPMG) sequence in a piecewise manner. Solid-state [super 35]Cl NMR spectroscopy is used for the structural characterization of chlorine-containing transition-metal and main-group systems.

A series of rhodium(I) complexes containing iminopyridine ligands were prepared to examine their ability to catalyze the hydroboration of series of vinylarenes. The reactions via use of catecholborane and pinacolborane were found to proceed largely through a dehydrogenative borylation mechanism to give a number of boronated products.

The combination of bulky electron-rich phosphides and electron-deficient B[([C.sub.6][F.sub.5]).sub.2] fragments have produced phosphinoboranes that have undergone facile addition to [H.sub.2] to produce the phosphine-borane adducts ([R.sub.2]PH)(HB[R'.sub.2]). The molecular features required for [H.sub.2] uptake is shown to be the critical issue for the design of a fully recyclable [H.sub.2] storage material.

The transition metal-free addition of phosphinoboronate ester Ph2PBpin (pin = 1,2-O2C2Me4) to heterocumulenes including carbodiimides, isocyanates, isothiocyanates and carbon dioxide has been investigated. The corresponding 1,2-addition products were readily prepared at room temperature without the need of a catalyst or added base. Addition of methanol to the compounds derived from addition of Ph2PBpin to carbodiimides, isocyanates, and isothiocyanates resulted in traditional hydrophosphination products. The methodology developed in this study provides a simple and elegant route for the generation of a wide range of functionalized phosphines. The phosphinoboronate ester Ph2PBpin also selectively and reversibly adds to CO2 at room temperature in a 1,2-manner. [ABSTRACT FROM AUTHOR]

The transition metal-free addition of phosphinoboronate ester Ph2PBpin (pin = 1,2-O2C2Me4) to heterocumulenes including carbodiimides, isocyanates, isothiocyanates and carbon dioxide has been investigated. The corresponding 1,2-addition products were readily prepared at room temperature without the need of a catalyst or added base. Addition of methanol to the compounds derived from addition of Ph2PBpin to carbodiimides, isocyanates, and isothiocyanates resulted in traditional hydrophosphination products. The methodology developed in this study provides a simple and elegant route for the generation of a wide range of functionalized phosphines. The phosphinoboronate ester Ph2PBpin also selectively and reversibly adds to CO2 at room temperature in a 1,2-manner. [ABSTRACT FROM AUTHOR]

Reductive amination of salicylaldehyde or 3,5-di-tert-butylsalicylaldehyde and 1-adamantylamine using NaBH4 gave the corresponding aminoalcohols in high yields. Subsequent addition of one equivalent of H3B.SMe2 to the aminoalcohols, with loss of two equivalents of dihydrogen, resulted in the formation of adamantanyl oxazaborinanes (1a,b). The molecular structure of 1b was studied by a single crystal X-ray diffraction study. Crystals were obtained from a saturated Et2O solution and belong to the triclinic space group P1 with unit cell parameters a = 9.1267(4) Å; b = 11.676(2) Å; c = 12.240(3) Å; a = 66.840(3)°; β = 78.529(3)°; and γ = 67.354(3)°. The molecular structure of the addition product (2a) arising from maltol and 1a was also confirmed by single crystal X-ray diffraction. Crystals were obtained from a saturated 1:2 mixture of toluene/Et2O and belong to the orthorhombic space group Pna2(1) with unit cell parameters a = 18.519(6) Å; b = 17.315(5) Å; and c = 12.680(4) Å. The asymmetric unit contains two molecules that differ slightly in some of the dihedral angles. [ABSTRACT FROM AUTHOR]

The synthesis of phosphinoboronate esters containing a single PB bond is reported, together with preliminary reactivity studies towards a range of organic substrates. These compounds add readily to aldehydes, ketones, aldimines, and α,β-unsaturated enones to give primarily the corresponding 1,2-addition products containing a new PC bond. The first examples of transition-metal-catalyzed phosphinoborations of C-C multiple bonds in which PC and BC bonds are formed in a single step are also disclosed; allenes react by a highly regioselective 1,2-addition whereas terminal alkynes undergo a formal 1,1-addition. [ABSTRACT FROM AUTHOR]