Nine- and Eight-Vertex Polyhedral Dicarbaborane Chemistry: New arachno and hypho Dicarbaboranes from arachno-4,5-C2B7H13: Isolation and Characterization of the [arachno-4,5-C2B7H12]- and [hypho-7,8-C2B6H13]- Anions, and of the Neutral Ligand Derivatives exo-6-(MeNC)-arachno-4,5-C2B7H11 and exo-5-L-hypho-4,9-C2B7H13 (L = NMe3 and NEt3)

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Title:Nine- and Eight-Vertex Polyhedral Dicarbaborane Chemistry: New arachno and hypho Dicarbaboranes from arachno-4,5-C2B7H13: Isolation and Characterization of the [arachno-4,5-C2B7H12]- and [hypho-7,8-C2B6H13]- Anions, and of the Neutral Ligand Derivatives exo-6-(MeNC)-arachno-4,5-C2B7H11 and exo-5-L-hypho-4,9-C2B7H13 (L = NMe3 and NEt3)
Creators:
Jelínek, Tomáš
Holub, Josef
Štíbr, Bohumil
Fontaine, Xavier L. R.
Kennedy, John D.
Journal or Publication Title:
Collection of Czechoslovak Chemical Communications, 59, 7, pp. 1584-1595

Abstract

<p>Deprotonation of neutral <i>arachno</i>-4,5-C<sub>2</sub>B<sub>7</sub>H<sub>13</sub> (<strong>1</strong>) either with 1, 8-(NMe<sub>2</sub>)<sub>2</sub>C<sub>10</sub>H<sub>6</sub> (proton sponge, PS) or with a mixture of aqueous K<sub>2</sub>CO<sub>3</sub> and [NMe<sub>4</sub>]Cl leads to the isolation in high yield of the [<i>arachno</i>-4,5-C<sub>2</sub>B<sub>7</sub>H<sub>12</sub>]<sup>-</sup> anion (<strong>2</strong>). Isostructural with this anion is the ligand derivative <i>exo</i>-6-(MeNC)-<i>arachno</i>-4,5-C<sub>2</sub>B<sub>7</sub>H<sub>11</sub> (<strong>3</strong>), which is prepared in 20% yield from the reaction between <i>arachno</i>-4,5-C<sub>2</sub>B<sub>7</sub>H<sub>13</sub> and MeNC in dichloromethane. Under comparable conditions compound <strong>1</strong> with tertiary amines gives the first representatives of the nine-vertex <i>hypho</i> family of dicarbaboranes, the ligand derivatives exo-5-(NR<sub>3</sub>)-<i>hypho</i>-4,9-C<sub>2</sub>B<sub>7</sub>H<sub>13</sub> (<strong>4a</strong> and <strong>4b</strong>, where R = Me and Et, respectively) in moderate yields (20 - 55%), whereas the reaction between <strong>1</strong> and aqueous NaCN results in the selective removal of one boron vertex to yield the eight-vertex [<i>hypho</i>-7,8-C<sub>2</sub>B<sub>6</sub>H<sub>13</sub>]<sup>-</sup> anion (<strong>5</strong>) in 61% yield. All compounds isolated were characterized by <sup>11</sup>B and <sup>1</sup>H NMR spectroscopy, with two-dimensional and selective decoupling techniques giving unambiguous assignments.

Title:Nine- and Eight-Vertex Polyhedral Dicarbaborane Chemistry: New arachno and hypho Dicarbaboranes from arachno-4,5-C2B7H13: Isolation and Characterization of the [arachno-4,5-C2B7H12]- and [hypho-7,8-C2B6H13]- Anions, and of the Neutral Ligand Derivatives exo-6-(MeNC)-arachno-4,5-C2B7H11 and exo-5-L-hypho-4,9-C2B7H13 (L = NMe3 and NEt3)
Creators:
Jelínek, Tomáš
Holub, Josef
Štíbr, Bohumil
Fontaine, Xavier L. R.
Kennedy, John D.
Divisions:Life and Chemical Sciences > Institute of Organic Chemistry and Biochemistry > Collection of Czechoslovak Chemical Communications
Journal or Publication Title:Collection of Czechoslovak Chemical Communications
Volume:59
Number:7
Page Range:pp. 1584-1595
ISSN:0010-0765
E-ISSN:1212-6950
Publisher:Institute of Organic Chemistry and Biochemistry
Related URLs:
URLURL Type
http://dx.doi.org/10.1135/cccc19941584UNSPECIFIED
ID Code:580
Item Type:Article
Deposited On:06 Feb 2009 17:02
Last Modified:06 Feb 2009 16:02

Citation

Jelínek, Tomáš; Holub, Josef; Štíbr, Bohumil; Fontaine, Xavier L. R.; Kennedy, John D. (1994) Nine- and Eight-Vertex Polyhedral Dicarbaborane Chemistry: New arachno and hypho Dicarbaboranes from arachno-4,5-C2B7H13: Isolation and Characterization of the [arachno-4,5-C2B7H12]- and [hypho-7,8-C2B6H13]- Anions, and of the Neutral Ligand Derivatives exo-6-(MeNC)-arachno-4,5-C2B7H11 and exo-5-L-hypho-4,9-C2B7H13 (L = NMe3 and NEt3). Collection of Czechoslovak Chemical Communications, 59 (7). pp. 1584-1595. ISSN 0010-0765

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