69739-34-0Relevant articles and documents
A method to derivatize surface silanol groups to Si-alkyl groups in carbon-doped silicon oxides
Darmakkolla, Srikar Rao,Tran, Hoang,Gupta, Atul,Rananavare, Shankar B.
, p. 93219 - 93230 (2016)
A carbon-doped silicon oxide (CDO) finds use as a material with a low dielectric constant (k) for copper interconnects in multilayered integrated circuits (ICs). Hydrophilic silanol groups (Si-OH) on its surface, however, can attract moisture, thereby causing an undesirable increase in the dielectric constant. Modification of the exposed hydrophilic surface to a hydrophobic functional group provides one solution to this problem. We report here a strategy for converting surface Si-OH to hydrophobic silicon hydride (Si-H) without affecting the internal oxide network in CDO. The approach involves esterification of the exposed silanol to its triflate (silyltrifluoromethanesulfonate, Si-O-Tf), followed by reduction to Si-H with diisobutylaluminum hydride. Si-H is further modified by a photochemical reaction with an alkene (1-octadecene) to yield Si-R (R = -C18H37) to provide a more moisture resistant, and less polar Si-C as opposed to the Si-O backbone. Fourier transform infrared (FT-IR) spectroscopy, X-ray photoelectron spectrometry (XPS), and measurements of the contact angle with water substantiated the successful conversion. The reaction scheme is versatile, transforming silanol groups to silicon hydride in widely varying chemical sites, from small molecules to the surfaces of silica gels, SiOx and CDO wafers. A comparison with the films (self-assembled monolayers) derivatized with the octadecyltrichlorosilane indicated that the new method leads to a thicker (≈5 nm) but more loosely packed hydrocarbon film with slightly lower contact angles.
Chemoselective silyl transfer in the Mukaiyama aldol reaction promoted by super silyl Lewis acid
Sai, Masahiro,Akakura, Matsujiro,Yamamoto, Hisashi
supporting information, p. 15206 - 15208 (2015/01/08)
In the silyl Lewis acid-promoted Mukaiyama aldol reaction, the steric and electronic properties of the silyl group on the silyl Lewis acid influence the reaction mechanism and product distribution. When super silyl triflates such as (TMS)3SiOTf and (TES)3SiOTf are used as Lewis acids, the silyl group of the silyl enol ether chemoselectively transfers to the product. The mechanistic details have been investigated using density functional theory (DFT) calculations.
Process for producing novel naphthyridine derivatives
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, (2008/06/13)
A novel naphthyridine derivative showing high activity as a tachykinin receptor antagonist can be produced at high efficiency by reacting an acylating agent such as a carboxylic acid derivative with a compound represented by the formula (1): wherein R1, R2 and R3 represent independently a hydrogen atom, a lower alkyl group, a lower alkoxyl group, an aryl group, a heteroaryl group, an amino group, etc., and X1 and X2 represent respectively a halogen atom.
