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  • 1
  • 2
    ISSN: 1432-1130
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract As an alternative to volumetric analysis, 11B NMR spectroscopy can be used to determine the hydride concentration and the relative amount of different active hydride species in mixtures of alkyldiboranes(6) (alkyl = Et, Pr). Inorganic selenium(IV) compounds react with propyldiboranes(6) at first to give elemental selenium (hydride number HN = 4) and after prolonged heating at 130 °C to selenides (HN = 6). In contrast, tellurium(IV) and tellurium(VI) compounds are reduced only to elemental tellurium.
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  • 3
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Boron Compounds, XXXVIII.  -  Regioselective O-Derivatization of D-Mannitol with the Aid of Ethylboron Protective Groups1,2: 3,4: 5,6-Tris(O-ethylboranediyl)-D-mannitol (3) is obtained in 80-98% yield by five routes involving D-mannitol and ethylboron compounds. 1,2,3,4,5,6-Hexakis(O-diethylboryl)-D-mannitol (1) and 1,2,5,6-tetrakis-(O-diethylboryl)-3,4-(O-ethylboranediyl)-D-mannitol (2) can be isolated as intermediates. The partial deborylation of 3 with methanol and of 2 with acetylacetone yields 3,4-(O-ethylboranediyl)-D-mannitol (4). The O-acylation of 4 gives the boron-containing compounds 5a and 5b and the boron-free 0-acyl-O-mannitol derivatives 6a, 6b and 7 in good yield.
    Notes: Aus D-Mannit und Äthylborverbindungen erhält man auf fünf verschiedenen Wegen isomerenfreien 1,2: 3,4: 5,6-Tris(O-äthylborandiyl)-D-mannit (3) in Ausbeuten von 80-98%. 1,2,3,4,5,6-Hexakis(O-diäthylboryl)-D-mannit (1) und 3,4-(O-Äthylborandiyl)-1,2,5,6-tetrakis- (O-diäthylboryl)-D-mannit (2) lassen sich als Zwischenprodukte Isolieren. Partielle Entborylierungen von 2 mit Acetylaceton oder von 3 mit Methanol liefern den 3,4-(O-Äthylborandiyl)-D-mannit (4). Durch O-Acylierung sind aus 4 die Borverbindungen 5a und 5b sowie die borfreien O-Acylderivate 6a, 6b und 7 gut zugänglich.
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  • 4
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 120 (1987), S. 1105-1115 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Reactions of (Organo)phosphorus-Oxygen Compounds with Diorgarno-hydro-boranes1)Trialkyl phosphites P(OR)3 [R=CH3 (2a), C2H5 (2b), CH(CH3)2 (2c), C4H9 (2d)] react with tetraalkyldiboranes(6) (R′2BH)2 [R′=C2H5 (1a)2, C3H7 (1b)2] in a temperature-dependent manner between 20 and 130°C to form the trialkyl phosphite-boranes (RO)3P-BHR′2, (RO)3P-BH2R′, and (RO)3P-BH3, which have various stabilities toward alcohols. With bis(9-borabicyclo-[3.3.1]nonane) (1c)2 the easily protolyzed addition compounds are obtained [e.g. 2a-1c, 2c-1c]. - Diorgano phosphites (RO)2P(O)H [R=CH3 (3a), C4H9 (3b), C6H5 (3c), CH2C6H5 (3d)], triorgano phosphates (RO)3PO [R=CH3 (4a), C4H9 (4b), C6H5 (4c), 2-CH3C6H4 (4d)], and the monosaccharide-diphenyl phosphates 4f, 4g, and 4h are reduced by (1a)2 or (1c)2 to give H2, PH3, and insoluble yellow phosphorus compounds, respectively. Phosphoric acid (4e), their derivatives OP(OBR2)3 [R=C2H5 (4ea), R2=C8H14 (4ec)], and phenylphosphonic acid C6H5P(O)-(OH)2 (6) are not deoxygenated at 130°C by (1a)2 to (1c)2. - Diorganophosphinic acids R2P(O)OH [R=C6H5 (5a), c-C6H11 (5b)] and phenylphosphinic acid C6H5(H)P(O)OH (5c) are reduced by (1a)2-(1c)2. Reaction of 5a with (1a)2 leads to the compounds [(C6H5)2P(BH3)O]B(C2H5)2 (8a-BH3), [(C6H5)2P-(BH3)O]BC2H5 [9a-(BH3)2], and [(C6H5)2P(BH3)O]3B [10-(BH3)3]. 5a reacts with (1c)2 under simultaneous formation of (C6H5)2PH (7) or (C6H5)2PH-HBC8H14 (7-1c) and (C6H5)2-POBC8H14 (8c) or (C6H5)2P(OBC8H14)-HBC8H14 (8c-1c). - 6 reacts with tetraethyldiboroxane (11a) to form a mixture of the oligomeric compounds -P(C6H5)(O)OB(C2H5)O]n-(6′a)n.
    Notes: Trialkylphosphite P(OR)3 [R=CH3 (2a), C2H5 (2b), CH(CH3)2 (2c), C4H9 (2d)] reagieren mit Tetraalkyldiboranen(6) (R′2BH)2 [R′=C2H5 (1a)2, C3H7 (1b)2] in Abhängigkeit von der Temperatur (20 bis 130°C) unter Bildung der gegenüber Alkoholen unterschiedlich stabilen Trialkylphosphit-Borane (RO)3P-BHR′2, (RO)3P-BH2R′ und (RO)3P-BH3. Mit Bis(9-borabicyclo-[3.3.1]nonan) (1c)2 erhält man die protolytisch leicht spaltbaren Additionsverbindungen [z.B. 2a-1c, 2c-1c]. - Diorganophosphite (RO)2P(O)H [R=CH3 (3a), C4H9 (3b), C6H5 (3c), CH2C6H5 (3d)], Triorganophosphate (RO)3PO [R=CH3 (4a), C4H9 (4b), C6H5 (4c), 2-CH3C6H4 (4d)] sowie die Monosaccharid-Phosphorsäure-diphenylester 4f, 4g und 4h werden von (1b)2 bzw. (1c)2 unter Bildung von H2, PH3 und/oder unlöslichen, gelben Phosphor-Produkten reduziert. - Phosphorsäure (4e), deren Derivate OP(OBR2)3 [R=C2H5 (4ea), R2=C8H14 (4ec)] und Phenylphosphonsäure C6H5P(O)(OH)2 (6) lassen sich von (1a)2 - (1c)2 bis 130°C nicht desoxygenieren. - Diorganophosphinsäuren R2P(O)OH [R=C6H5 (5a), c-C6H11 (5b)], Phenylphosphinsäure C6H5(H)P(O)OH (5c) werden von (1a)2 bis (1c)2 reduziert. 5a und (1a)2 bilden [(C6H5)2P(BH3)O]B(C2H5)2 (8a-BH3), [(C6H5)2P(BH3)O]2BC2H5) [9a - (BH3)2] und [(C6H5)2P(BH3)O]3B [10-(BH3)3]. Mit (1c)2 reagiert 5a unter gleichzeitiger Bildung von (C6H5)2PH (7) bzw. (C6H5)2PH-HBC8H14 (7-1c) sowie von (C6H5)2POBC8H14 (8c) bzw. (C6H5)2P(OBC8H14)-HBC8H14 (8c-1c). - 6 bildet mit Tetraethyldiboroxan (11a) ein Gemisch oligomerer - [P(C6H5)(O)OB(C2H5)O]n-Verbindungen (6′a)n.
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  • 5
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 122 (1989), S. 677-686 
    ISSN: 0009-2940
    Keywords: Acetoxyhdroarenes ; Anthracene ; Borylhydroarenes ; Naphthalene ; Hydroboration ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Reduction of Polycyclic Arenes with -Boranes, I. - Reactions of Naphthalene, Anthracene, and Phenanthrene with Tetraalkyldiboranes(6)Polycyclic arenes, e.g. naphthalene (N3), acenaphthene, anthracene (A3), naphthacene, benzo[a]anthracene, and 3,4-benzophenanthrene react without gas evolution irreversibly with organodiboranes(6) [tetraethyldiborane(6) (TEDB), and tetrapropyldiborane(6) (TPDB)] at T ≥ 130°C to form borylated hydroarenes and their functional derivatives. The uptake of borane (TPDB) is followed by analytical methods. The reactions carried out on preparative scale with N3 and either TPDB or TEDB (2-10 h, T ≥ 140°C) result in a mixture of borylated C10 compounds, from which after oxidation and O-acetylation 1- and 2- acetoxytetralins (N4, N5), together with small amounts of tetralin (N1), can be isolated. A3 reacts forming tetrahydroanthracene (A1), 1-, and 2-acetoxytetrahydroanthracene (A4, A6) as well as single stereoisomers of 1,4- and 1,3-diacetoxytetrahydroanthracene (A10, A13), which were separated and characterized. On extended heating (64 h) of A3 with TPDB at T ≥ 140°C, the main products are one regioisomer of acetoxyhexahydroanthracene (A5) and 6 isomers of diacetoxyoctahydroanthracene (A7-A9, A11, A12, A14). For the formation of N4, N5, A4, A6-A9, A11, A12, and A14 (deuteration experiments), a hydroboration of the arene and subsequent hydrodeboration are suggested. Organo polyboranes and/or carboranes of unknown structures are formed as sideproducts. Phenanthrene (PH), which appears to be unreactive at 130°C, was shown to undergo a slow deuterioboration/dehydroboration on treatment with [D2]TEDB at 150°C resulting in the deuterated compounds [9-D1]PH and [9,10-D2]PH.
    Notes: Kondensierte Arene wie Naphthalin (N3), Acenaphthen, Anthracen (A3), Naphthacen, Benz[a]anthracen und 3,4-Benzphenanthren reagieren mit Organodiboranen(6) [Tetraethyldiboran(6) (TEDB), Tetrapropyldiboran(6) (TPDB)] bei T ≥ 130°C ohne Gasabspaltung irreversibel zu borylierten Hydroarenen und deren funktionellen Derivaten. Die -Boran-Reaktion der Arene mit TPDB wird analytisch verfolgt. Aus N3 erhält man mit TPDB oder TEDB ein Gemisch borylierter C10-Verbindungen, aus dem sich nach Oxidation/O-Acetylierung 1- und 2-Acetoxytetralin (N4, N5) sowie wenig Tetralin (N1) isolieren lassen. A3 reagiert zu Tetrahydroanthracen (A1), 1- und 2-Acetoxytetrahydroanthracen (A4, A6) sowie zu den stereoeinheitlichen, charakterisierten 1,4- und 1,3-Diacetoxytetrahydroanthracenen (A10, A13). Nach 64 h werden aus A3 mit TPDB bei T ≥ 140°C ein regioeinheitliches Acetoxyhexahydroanthracen (A5) sowie 6 isomere Diacetoxyoctahydroanthracene (A7-A9, A11, A14) erhalten. N4, N5 sowie A4, A6-A9, A11, A12 und A14 bilden sich (Deuterierungsexperimente) durch Hydroborierung der Arene und nachfolgende Hydrodeborierung. Nebenprodukte sind Organo-polyborane und/oder -carborane unbekannter Struktur. Das bei 130°C gegenüber -Boranen reduktionsstabil erscheinende Phenanthren (PH) wird von [D2]TEDB bei 150°C unter Deuterioborierung/Dehydroborierung langsam in die deuterierten Verbindungen [9-D1]PH und [9,10-D2]PH umgewandelt.
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  • 6
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 124 (1991), S. 2259-2262 
    ISSN: 0009-2940
    Keywords: Hydroborate ; triethyl ; sodium salt ; Sodium  -  arene addition compound ; Mesitylene ; Tricoordinated H atoms ; Solid-solid phase transformation ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Crystalline Sodium Triethylhydroborate  -  Formation and CharacterizationTwo equiv. of NaHBEt3 (1) and one equiv. of mesitylene form a crystalline compound, which is characterized by DSC and by a single-crystal X-ray structure analysis at 190 K as the solid phase 2.
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  • 7
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 127 (1994), S. 1593-1598 
    ISSN: 0009-2940
    Keywords: Boryl sulfates, diethyl-, 9-BBN- ; Sulfatoboranes ; Ethylboronic acid, sulfuric acid, mixed anhydrides of ; Sulfatization of boranes ; Diboroxane, cyclic ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Organoboryl Sulfates  -  Preparation and Characterisation[1]Triethylborane (3) reacts with sulfuric acid to form the sulfate Et2BOS(O2)OBEt2 (1a), which can also be prepared from (Et2B)2O (4a) and SO3. Sulfate 1a reacts with (C8H14B)2O (4b) to give the solid sulfate C8H14BOS(O2)OBC8H14 (1b) and 4a. Compound 1b is also obtained by treating 4b with SO3. The reaction of 4a with sulfuric acid leads to the crystalline cyclic sulfate EtBOB(Et)OS(O2)O (2a) (X-ray structure analysis). 2a is also available from triethylboroxin (5) on reaction with SO3. The diboroxanes 4a and 4b and H2SO4 form insoluble 1:1 addition complexes 4a·H2SO4 and 4b·H2SO4, which react on heating at about 60°C to yield the cyclic sulfates 2a and C8H15BOB(C8H15)OS(O2)O (2b), respectively.
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  • 8
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 127 (1994), S. 1843-1849 
    ISSN: 0009-2940
    Keywords: Amine-Diboroxanes, bicyclic ; 1,2-Deaminoboration, intramolecular ; Deoxyboration ; Allyl-aminoboranes, organosubstituted, rearrangement ; C-Borylation ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Rearrangement and Degradation of Bicyclic Amine-Tetraalkyldiboroxanes[1]The amine-tetraalkyldiboroxanes [1a: R1,4,7,7′ = Et; 1b: R1,4,7 = Et, R7′ = Ph; 1b′: R4,7,7′ = Et,R1 = Ph; 1c: R1,7,7′ = Et, R4 = Ph] react on heating by EtBO elimination and allylborane rearrangement to yield the allyl-aminoboranes Me2NB(Et)CH2C(R4)=C(R7,7′) [2a: R4,7,7′ = Et; 2b/2b′: R4 = Et, R7,7′ = Et, Ph; 2c: R4 = Ph, R7,7′ = Et]: On heating above 60°C the diastereomeric syn/anti-Id/1d′(Id: R1,7 = C8H14, R4,7′ = Et; 1d′: R1,7′ = C8H14, R4,7 = Et) give the unsaturated rac-amino-trialkyldiboroxane (rac-3) (X-ray structure analysis) by intramolecular 1,2-deaminoboration. rac-3 is characterized by reaction with (Et2BH)2 and (Et2BD)2 with formation of the 1,2,6-oxadiborinane 5 by evolution of H2 or HD respectively. The intramolecular CH-borylation of rac-3 is compared with those of the thujopsen hydrocarbons I-III.
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  • 9
    ISSN: 0009-2940
    Keywords: Ethylboronic carboxylic acid anhydrides, comproportionation of ; Bicyclo[3.3.1]nonadienes, heteroatom-containing ; Bicyclo[3.3.3]undecadienes, heteroatom-containing ; 1,3,2-Diboroxanes ; Oxygen atom exchange ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Chelate-Stabilized 1,3-Bis(acyloxy)-1,3-diethyldiboroxanes from Triethylboroxin and Carboxylic Acid AnhydridesTriethylboroxin (A) reacts with carboxylic acid anhydrides (RCO)2O [R = Me: 1a; Et: 1b; tBu: 1d; Ph: 1e] with various rates to give high yields of the 3,7-dialkyl-1,5-diethyl-4,8,9-trioxa-2,6-dioxonia-1,5-diboratabicyclo[3.3.1]nona-2,6-dienes OB(Et)OC(R)OB(Et)OC(R)O (2) [R = Me: 2a (X-ray crystal structure analysis); Et: 2b; tBu: 2d; Ph: 2e], presumably via the unstable compounds OB(Et)OB(Et)OC(R)OB(Et)OC(R)O (3a,b, d, e). Compound 1c (R = CF3) reacts with A to form a mixture of 1,3-diethyl-1,3-bis(trifluoroacetoxy)diboroxane O=C(CF3)OB(Et)OB(Et)O(CF3)C=O (2c′) and 2c (R = CF3) at room temperature. Whereas two compounds of the type 2 do not comproportionate, 1a-e spontaneously form the mixed substituted carboxylic acid anhydrides 1ab etc. on mixing at room temperature (GC, 13C NMR). - From the 17O-enriched A* and 1a-e the 17O-enriched compounds 2a*-e* with BO*B and YYBO*OCR groups are obtained. A* exchanges O atoms up to 200°C with succinic anhydride (1f) forming 1f* or with phthalic acid anhydride (1g) forming 1g* and 3g*. - The mixed carboxylic acid anhydrides 1xy are cleaved, and the mixtures of 1 are separated with A to yield the uniform 3,7-dialkyl-substituted compounds 2.
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  • 10
    ISSN: 0009-2940
    Keywords: Selenium dioxide, 1,2-ethyloboration ; Selenium diimide, 1,2-ethyloboration ; Seleninic acid, ethane- ; Transborylation, OBEt2, O-9-BBN ; Ethene, elimination ; Amino(diethyl)boranes ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Both selenium dioxide (1) and selenium bis(tert-butylimide) (2) react with triethylborane (A) by 1,2-ethyloboration. In the case of 1, ethane, ethene, diethylselane (4a), tetraethyldiboroxane (Et2B)2O (B), triethylboroxine (EtBO)3 (D) and a cyclic compound [-Et2BOSe(Et)O-]2 (52) are formed after heating to 65°C. Compound 52 is also formed when 1 reacts with B. Treatment of selenous acid (3) with A or, preferentially for synthetic purposes, with B provides further routes to 52. The reaction of the diimide 2 with A starts already below -50°C: a cyclic ethaneselenic acid derivative 6, Et2BN(tBu)-Se(Et)NtBu, is formed, and 6 starts to decompose at -50°C by elimination of ethene to give finally (tert-butylamino)diethylborane (8), bis(diethylboryl)-tert-butylamine (9), and Et2Se (4a). Transborylation of 52 with (9-BBN)2O (C) affords [-(9-BBN)OSe(Et)O-]2 (102), which crystallizes in the monoclinic space group P21/n with the lattice constants (118 K) a = 667.1(1), b = 1282.5(1), c = 1289.1(1) pm and β = 93.06(1)°. All reactions were monitored by 11B- and 77Se-NMR spectroscopy. Furthermore, the reactions of 1 with A and B and the transborylations were studied by 17O-NMR spectroscopy using the 17O-enriched compounds 1(17O), B(17O), C(17O), and D(17O).
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