催化碳化β-乳酸盐到酸无水化物
Yutan D Y L Getzler1, Vinod Kundnani, Emil B Lobkovsky
1Department of Chemistry and Chemical Biology, Baker Laboratory, Cornell University, Ithaca, New York 14853-1301, USA.
Journal of the American Chemical Society
|June 4, 2004
概括
一种新的-催化剂有效地从一氧化碳 (CO) 和β-乳酸盐中合成酸无水化物. 这种催化剂表现出高活性和选择性,在反应中观察到立体化学控制.
科学领域:
- 催化剂是一种催化剂.
- 有机合成 有机合成
- 有机金属化学 有机金属化学
背景情况:
- 酸无水化物是有价值的化学中间体.
- 从易于获得的前体中有效合成酸无水化物是可取的.
- 现有的催化方法可能缺乏选择性或需要恶劣的条件.
研究的目的:
- 开发一种高活性和选择性催化剂,用于酸无水化物合成.
- 用一氧化碳 (CO) 研究β-乳酸盐的催化碳化.
- 阐明催化过程的机制和立体化学结果.
主要方法:
- 一种新型-催化剂的合成和表征: [(N,N'-bis(3,5-di-tert-butylsalicylidene) phenylenediamino) Al ((THF) 2) [Co ((CO) 4].
- 各种β-乳酸的催化碳化反应与200psi的CO.
- 使用光谱方法分析反应产品并确定立体化学.
主要成果:
- 催化剂可以高效地将β-propiolactones转化为酸无水化物.
- (R) - 贝塔 - 丁烯被转化为 (S) - 甲基苏酸无水化物,完全逆转了立体化学反应.
- cis-2,3-二甲基-β-propiolactone 完全产生了跨-2,3-二甲基糖化物.
结论:
- 已经开发出一种明确的,高度活性和选择性的催化剂,用于从二氧化碳和β-乳酸盐中合成酸无水化物.
- 催化过程以可预测的立体化学控制进行,表明了特定的反应机制.
- 拟议的机制涉及[Co(CO) 4) - 对β-乳酸的核友性攻击,随后是CO插入和无水化物形成.
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