Synthesis, Structural Characterization, and Reactivity Studies of 5-CF3SO3-B10H13
摘要:
In contrast to previous reactions carried out in cyclopentane solvent at room temperature that produced 6-TfO-B10H13 (TfO = CF3SO3), the reaction of c/oso-B10H102- with a large excess of trifluoromethanesulfonic acid in the ionic liquid 1-butyl-3-methylimidazolium trifluoromethanesulfonate (bmimOTf) gave exclusively the previously unknown S-TfO-B10H13 isomer. Experimental and computational studies demonstrated that the difference in the products of the two reactions is a result of 6-TfO-B10H13 isomerizing to S-TfO-B10H13 above room temperature in bmimOTf solutions. Reactivity studies showed that 5-TfO-B10H13: (1) is deprotonated by reaction with 1,8-bis(dimethylamino)naphthalene to form the S-TfO-B10H121- anion; (2) reacts with alcohols to produce 6-RO-B10H13 boryl ethers (R = Me and 4-CH3O-C6H4); (3) undergoes olefin-hydroboration reactions to form 5-TfO-6,9-R-2-B10H11 derivatives; and (4) forms a 5-TfO-6,9-(Me2S)(2)-B10H11 adduct at its Lewis acidic 6,9-borons upon reaction with dimethylsulfide. The S-TfO-6,9-(Me2S)(2)-B10H11 adduct was also found to undergo alkyne-insertion reactions to form a range of previously unreported triflate-substituted 4-TfO-ortho-carboranes (1-R-4-TfO-1,2-C2B10H10) and reactions with triethylamine or ammonia to form the first TfO-substituted decaborate [R3NH+](2)[2-TfO-B10H92-], and [R3NH+](2)[1-TfO-B10H92-] (R = H, Et) salts.
酸诱导的[ closo -B 10 H 10 ] 2–的开放,是向6位取代的Nido -B 10 H 13癸烷和相关碳硼烷的新途径
摘要:
多面体阴离子[ closo -B 10 H 10 ] 2–在超酸性条件下的质子化显然会生成亲电子中间体[B 10 H 13 ] +,形成6-R-氨基-B 10 H 13(R =芳基,烷基,三氟甲磺酸酯)衍生物分别通过亲电芳香取代,CH键活化或离子对塌陷。拟议的通过硼酸化[B 10 H 13 ] +形成6-R-氨基-B 10 H 13衍生物的机理讨论。描述了从6-R-氨基-B 10 H 13十硼烷开始的碳硼烷的合成,以及几种6-R-氨基-B 10 H 13十硼烷和碳硼烷的单晶X射线衍射分析。