Selective dismantling of closo-1,2-C2B10H12 to lower-cage dicarbaborane systems

[img]PDF - Authorized users only
Language: English
765Kb
Title:Selective dismantling of closo-1,2-C2B10H12 to lower-cage dicarbaborane systems
Creators:
Plešek, Jaromír
Štíbr, Bohumil
Fontaine, Xavier L. R.
Kennedy, John D.
Heřmánek, Stanislav
Jelínek, Tomáš
Journal or Publication Title:
Collection of Czechoslovak Chemical Communications, 56, 8, pp. 1618-1635

Abstract

A modified, high-yield synthesis of the two isomeric <i>nido</i> twelve-vertex [C<sub>2</sub>B<sub>10</sub>H<sub>13</sub>]<sup>-</sup> anions, "reactive" [<i>nido</i>-7,9-C<sub>2</sub>B<sub>10</sub>H<sub>13</sub>]<sup>-</sup> and "unreactive" [<i>nido</i>-7,12-C<sub>2</sub>B<sub>10</sub>H<sub>13</sub>]<sup>-</sup>, has been developed. A solution structure for the reactive [<i>nido</i>-7,9-C<sub>2</sub>H<sub>10</sub>B<sub>13</sub>]<sup>-</sup> isomer is proposed on the basis of the result of two-dimensional <sup>11</sup>B and <sup>1</sup>H correlation NMR spectroscopy. It is concluded that there is a marked similarity between this species and the eleven-vertex congener [<i>nido</i>-7,8-C<sub>2</sub>B<sub>9</sub>H<sub>12</sub>]<sup>-</sup>. In accord with this parallel, the "reactive" twelve-vertex species is found to undergo selective boron-vertex elimination reactions in the presence of oxidizing agents. These reactions give excellent yields of smaller-cage <i>nido</i> dicarbaborane compounds, namely [<i>nido</i>-7,8-C<sub>2</sub>B<sub>9</sub>H<sub>12</sub>]<sup>-</sup>, [9-(SMe<sub>2</sub>)-<i>nido</i>-7,8-C<sub>2</sub>B<sub>9</sub>H<sub>11</sub>], and <i>nido</i>-5,6-C<sub>2</sub>B<sub>8</sub>H<sub>12</sub>. NMR spectroscopy assigns cluster <sup>11</sup>B and <sup>1</sup>H resonances for all the compounds isolated, and thence permits comparison with the equivalent shielding patterns of structurally related analogues such as [<i>nido</i>-7-CB<sub>10</sub>H<sub>13</sub>]<sup>-</sup> and [<i>nido</i>-7,9-C<sub>2</sub>B<sub>9</sub>H<sub>12</sub>]<sup>-</sup>.

Title:Selective dismantling of closo-1,2-C2B10H12 to lower-cage dicarbaborane systems
Creators:
Plešek, Jaromír
Štíbr, Bohumil
Fontaine, Xavier L. R.
Kennedy, John D.
Heřmánek, Stanislav
Jelínek, Tomáš
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:56
Number:8
Page Range:pp. 1618-1635
ISSN:0010-0765
E-ISSN:1212-6950
Publisher:Institute of Organic Chemistry and Biochemistry
Related URLs:
URLURL Type
http://dx.doi.org/10.1135/cccc19911618UNSPECIFIED
ID Code:5088
Item Type:Article
Deposited On:22 Feb 2010 11:30
Last Modified:22 Feb 2010 10:30

Citation

Plešek, Jaromír; Štíbr, Bohumil; Fontaine, Xavier L. R.; Kennedy, John D.; Heřmánek, Stanislav; Jelínek, Tomáš (1991) Selective dismantling of closo-1,2-C2B10H12 to lower-cage dicarbaborane systems. Collection of Czechoslovak Chemical Communications, 56 (8). pp. 1618-1635. ISSN 0010-0765

Repository Staff Only: item control page