The structure of a new isomer of dicarba-nido-undecaborane(13)

Struchkov, Yu. T.; Antipin, M. Yu.; Stanko, V. I.; Brattsev, V. A.; Kirillova, N. I.; Knyazev, S. P.

doi:10.1016/s0022-328x(00)92266-6

Cited by 21 publications

(11 citation statements)

References 11 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The molecular geometry of nido-7-Me-2,8-C 2 B 9 H 12 was previously proposed 19,21 on the basis of cage rearrangement mechanisms determined for the formation of the structurallyknown neutral nido-11-Me-2,7-C 2 B 9 H 12 . 24 Here we find that nido-7-Me-2,8-C 2 B 9 H 12 is the only isomer compatible with the cross peaks observed in the 2D 11 B-11 B{ 1 H} COSY spectrum of 7.…”

Section: Resultssupporting

confidence: 73%

“…Best fitting between the experimental (X-ray) 24 Ϫ containing an endo-methyl group like in XXVIIa (Fig. 5) has been determined by X-ray crystallography.…”

Section: Computational Studiesmentioning

confidence: 98%

“…22 Geometries of the air-sensitive 11-vertex closo-carboranes formed in this study were determined by multinuclear NMR spectroscopy and confirmed where possible by the reliable ab initio/GIAO/NMR method. 23 In addition 11-vertex geometries of B-methyl-nido-carboranes (where only the neutral carborane nido-11-Me-2,7-C 2 B 9 H 12 is structurally determined 24 ) were deduced by these methods.…”

mentioning

confidence: 99%

See 2 more Smart Citations

Cage-closing reactions of the nido-carborane anion 7,9-C2B9H12− and derivatives; formation of neutral 11-vertex carboranes by acidification

Fox

Hughes

Malget

2002

J. Chem. Soc., Dalton Trans.

View full text Add to dashboard Cite

B 9 H 10 (X = Cl, I), are formed from reactions of salts containing 1(6)-X-7,9-C 2 B 9 H 11 Ϫ anions with H 2 SO 4 , and 4-F-2,3-( p-FC 6 H 4 ) 2 -2,3-C 2 B 9 H 8 is formed from (Bu 4 N)(3-F-7,9-( p-FC 6 H 4 ) 2 -7,9-C 2 B 9 H 9 ) and F 3 CSO 3 H. Elimination of the ethoxide and fluoride substituents from the cage occurs during acidification of salts containing 10-OEt-7,9-C 2 B 9 H 11 Ϫ and 10-F-7,9-( p-FC 6 H 4 ) 2 -7,9-C 2 B 9 H 9 Ϫ by F 3 CSO 3 H, resulting in the closo-carboranes 2,3-C 2 B 9 H 11 and 2,3-( p-FC 6 H 4 ) 2 -2,3-C 2 B 9 H 9 as major products respectively. A mixture of B-Me-2,3-C 2 B 9 H 10 isomers is obtained from salts containing the 8-Me-7,9-C 2 B 9 H 11 Ϫ and 10-Me-7,9-C 2 B 9 H 11 Ϫ anions with H 2 SO 4 . B-Me-2,3-C 2 B 9 H 10 is suggested to be fluxional in solution with 4-Me-2,3-C 2 B 9 H 10 as the major component. Protonation of the fluxional anion 10(11)-endo-Me-7,9-C 2 B 9 H 11 Ϫ with acetic acid gives a neutral nido-carborane 11-Me-2,8-C 2 B 9 H 12 rather than closo-B-Me-2,3-C 2 B 9 H 10 . Molecular geometries of 11-vertex closo-carboranes and B-methyl-nido-carboranes are determined by the combined ab initio/GIAO/NMR method at the GIAO-B3LYP/6-311G*//MP2/6-31G* level of theory. Scheme 1 The reactions of nido-7,9-C 2 B 9 H 12 Ϫ 1a and nido-7,8-C 2 B 9 H 12 Ϫ with acid and the synthesis of closo-2,3-C 2 B 9 H 11 2a showing the cage numbering. Exo-hydrogens are omitted for clarity. DALTON

show abstract

Section: Resultssupporting

confidence: 73%

“…Best fitting between the experimental (X-ray) 24 Ϫ containing an endo-methyl group like in XXVIIa (Fig. 5) has been determined by X-ray crystallography.…”

Section: Computational Studiesmentioning

confidence: 98%

mentioning

confidence: 99%

See 1 more Smart Citation

Cage-closing reactions of the nido-carborane anion 7,9-C2B9H12− and derivatives; formation of neutral 11-vertex carboranes by acidification

Fox

Hughes

Malget

2002

J. Chem. Soc., Dalton Trans.

View full text Add to dashboard Cite

show abstract

“…[20][21][22] The alkylations have been shown to proceed via cage isomers 11-R-2,7-nido-C 2 B 9 H 11 − , one of which (R = Me) could be isolated as a protonated species. 21,[23][24][25] 27,28 Herein, we demonstrate that sulfenyl chlorides also may act as appropriate reagents in electrophilic substitutions with 1 and give the expected asymmetric products in high yield.…”

Section: Introductionmentioning

confidence: 99%

Electrophilic substitution of the nido-dicarbaborate anion 7,8-nido-C2B9H12− with sulfenyl chlorides

et al. 2012

View full text Add to dashboard Cite

Sulfenyl chlorides RSCl (R = p-C(6)H(4)OMe, Ph, p-C(6)H(4)NO(2), CN or 2-C(5)H(4)N) react with 7,8-nido-C(2)B(9)H(12)(-) with asymmetric substitution on the pentagonal C(2)B(3) face to give 9-RS-7,8-nido-C(2)B(9)H(11)(-) (R = p-C(6)H(4)OMe (3), Ph (4), p-C(6)H(4)NO(2) (5), CN (6)) and the zwitterion 9-(S-2-C(5)H(4)NH)-7,8-nido-C(2)B(9)H(11) (7), respectively, in high yield, while tBuSCl did not react and S(2)Cl(2) led to decomposition. Further reaction of 5-7 with iodine gave the corresponding iodo derivatives NMe(4) [9-I-11-RS-7,8-nido-C(2)B(9)H(10)] (R = p-C(6)H(4)NO(2) (8), CN (9)) and the zwitterion 9-I-11-(S-2-C(5)H(4)NH)-7,8-nido-C(2)B(9)H(11) (10), respectively. Compounds 3-10 were fully characterised by (1)H, (11)B, (11)B{(1)H}, (13)C{(1)H} spectroscopy, IR spectroscopy, mass spectrometry and elemental analysis, 3-7 also by (11)B-(11)B{(1)H} COSY NMR spectroscopy and 8-10 by X-ray structure determination.

show abstract

“…12-14 For example, [3,3,3 ] and 2,9-C 2 B 9 H 13 respectively. 12, 13 We were attracted to the neutral B-methylated carborane 11-Me-2,7-C 2 B 9 H 12 4, [15][16][17][18] prepared from the reaction of nido-7,8-C 2 B 9 H 11 2Ϫ with MeI followed by acidification. The carborane can lead to three isomeric B-methylated nido carborane anions MeC 2 B 9 H 11 Ϫ on deprotonation.…”

Section: Introductionmentioning

confidence: 99%