Feige Felix, Kögel Julius F, Lork Enno, Beckmann Jens
Institut für Anorganische Chemie und Kristallographie, Universität Bremen, Leobener Straße 7, 28359 Bremen, Germany.
Dalton Trans. 2021 Dec 14;50(48):18186-18193. doi: 10.1039/d1dt03389a.
The reaction of the polyfluorinated lithium triarylmethanolates ArCOLi (Ar = CF, 3,5-(CF)CH) with SiCl provided the monosubstituted products ArCOSiCl (1a, Ar = CF; 1b, Ar = 3,5-(CF)CH). The hydrolysis of 1a and 1b produced the silanetriols ArCOSi(OH) (2a, Ar = CF; 2b, Ar = 3,5-(CF)CH) without the aid of an HCl scavenger. The reaction of two equivalents of ArCOLi (Ar = CF, 3,5-(CF)CH) with (ClSi)O afforded the disubstituted products [(CF)COSiCl]O (3a) and {[(3,5-(CF)CH)CO]SiCl}O (3b), the hydrolysis of which gave the corresponding disiloxanetetraols [(CF)COSi(OH)]O (4a) and [(3,5-(CF)CH)COSi(OH)]O (4b). At high concentrations in the presence of HCl, 2b undergoes controlled condensation to yield 4b. In the solid-state, 2a, 4a and 4b are mainly associated by hydrogen bonds of the type SiO-H⋯O(H)Si whereas the competing SiO-H⋯O(C)Si type was not observed.
多氟代三芳基甲醇锂盐ArCOLi（Ar = CF₃，3,5-(CF₃)₂CH）与SiCl₄反应得到单取代产物ArCOSiCl₃（1a，Ar = CF₃；1b，Ar = 3,5-(CF₃)₂CH）。1a和1b的水解在无需HCl清除剂的情况下生成硅三醇ArCOSi(OH)₃（2a，Ar = CF₃；2b，Ar = 3,5-(CF₃)₂CH）。两当量的ArCOLi（Ar = CF₃，3,5-(CF₃)₂CH）与(ClSi)₂O反应得到二取代产物[(CF₃)COSiCl₂]₂O（3a）和{[(3,5-(CF₃)₂CH)CO]SiCl₂}₂O（3b），它们水解得到相应的二硅氧烷四醇[(CF₃)COSi(OH)₂]₂O（4a）和[(3,5-(CF₃)₂CH)COSi(OH)₂]₂O（4b）。在HCl存在下高浓度时，2b发生可控缩合生成4b。在固态中，2a、4a和4b主要通过SiO-H⋯O(H)Si型氢键缔合，而未观察到竞争性的SiO-H⋯O(C)Si型氢键。
