甲硅烷基烯醇醚5和β-内酰胺9(R = Me 3 Si)偶联得到酮13a-d。化合物13a,13c和13d转化为三环内酰胺16-20、23-25。(光学纯的甲硅烷基烯醇醚5的化学酶法合成可得到同手性内酰胺23-25。)此外,酮氮杂环丁酮13被保护为1,3-恶唑烷30。使用Bouffard方法进行所需的立体化学反应,得到醇32。形成相应的碳酸硝基苄酯,脱保护和氧化提供了酮35a和35b,其随后分别转化为三苯甲基41a和41b。
REVERSIBLE BINDERS FOR USE IN BINDER JETTING ADDITIVE MANUFACTURING TECHNIQUES
申请人:General Electric Company
公开号:US20180071820A1
公开(公告)日:2018-03-15
A method of binder jet printing a metal part includes depositing a layer of a metal powder on a working surface of a binder jet printer and selectively printing a binder solution having a reversible binder into the layer of metal powder in a pattern to generate a printed layer. The pattern is representative of a structure of a layer of the metal part. The method also includes curing the reversible binder in the printed layer to generate a layer of a green body metal part and heating the green body metal part above a first temperature to remove a substantial portion of the reversible binder and generate a brown body metal part. The reversible binder is thermally decomposed to generate oligomers that remain within and strengthen the brown body metal part. The method further includes heating the brown body metal part above a second temperature to remove the oligomers and sinter the metal powder to generate the metal part. The metal part is substantially free of char residue.