支持基于Mo的合性复合物作为对enantioselectiveolefin转化物的有效催化剂
Sarah J Dolman1, Kai C Hultzsch, Frédéric Pezet
1Contribution from the Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
Journal of the American Chemical Society
|September 2, 2004
概括
合成了七种新的聚合物支持的基于 (Mo) 的性复合物,并对不对称的环闭和环开转化反应进行了测试. 这些催化剂具有很高的反应性和反选择性,产品中金属杂质减少.
科学领域:
- 有机金属化学 有机金属化学
- 聚合物化学 聚合物化学
- 不对称的催化剂.
背景情况:
- 开发高效且可回收的性催化剂对于可持续合成至关重要.
- 聚合物支持的催化剂在分离和净化方面具有优势.
- 基于的复合物以它们在转化反应中的催化活性而闻名.
研究的目的:
- 合成和表征新型聚合物支持的基于Mo的性复合物.
- 评估这些支持的催化剂在非对称环闭 (ARCM) 和环开 (AROM) 转化反应中的催化性能.
- 调查聚合物支性质,如交叉链接,对催化效率和选择性的影响.
主要方法:
- 合成基于聚乙烯和基于聚诺基的奇拉性Mo复合物.
- 在各种ARCM和AROM反应中测试催化活性.
- 对产品中的反应性,酶选择性和金属杂质水平的分析.
主要成果:
- 成功合成了七种新的聚合物支持的基于Mo的性复合物.
- 在ARCM和AROM反应中的催化活动与同质的对应物具有竞争力.
- 聚合物中较低的交叉链接支持增强的反应效率和不对称的诱导.
- 与同质催化剂产生的产品相比,产品的金属杂质明显较低.
结论:
- 聚合物支持的基性Mo基复合物是不对称转移的有效催化剂.
- 催化剂的可回收性和减少金属污染是其关键优势.
- 优化聚合物支特性可以进一步提高催化性能.
相关概念视频
Hydroboration-Oxidation of Alkenes
In addition to the oxymercuration–demercuration method, which converts the alkenes to alcohols with Markovnikov orientation, a complementary hydroboration-oxidation method yields the anti-Markovnikov product. The hydroboration reaction, discovered in 1959 by H.C. Brown, involves the addition of a B–H bond of borane to an alkene giving an organoborane intermediate. The oxidation of this intermediate with basic hydrogen peroxide forms an alcohol.
Alkynes to Aldehydes and Ketones: Hydroboration-Oxidation
Introduction
One of the convenient methods for the preparation of aldehydes and ketones is via hydration of alkynes. Hydroboration-oxidation of alkynes is an indirect hydration reaction in which an alkyne is treated with borane followed by oxidation with alkaline peroxide to form an enol that rapidly converts into an aldehyde or a ketone. Terminal alkynes form aldehydes, whereas internal alkynes give ketones as the final product.
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