甲酸,甲酸和甲酸-组装,结构和反应性
Gang Hu1, Anil K Gupta1, Li Huang1
1Department of Chemistry, Michigan State University , East Lansing, Michigan 48824, United States.
Journal of the American Chemical Society
|June 29, 2017
概括
该研究显示,BINOL配体形成各种酸盐物种,包括酸盐和螺旋酸盐,可以作为有效的不对称催化剂. 特定的BINOL衍生物,如3,3′-Ph2BINOL,在阿齐里迪纳反应中产生更高的催化性能.
科学领域:
- 有机金属化学
- 不对称的催化
- 化学
背景情况:
- VANOL和VAPOL连接物与B(OPh) 3形成有效的氧酸催化剂.
- 不同于VANOL/VAPOL,之前发现BINOL配体是B(OPh) 3的弱催化剂.
- 酸乙烯的酸是已知的性催化剂,存在于各种形式,如中酸和螺旋酸.
研究的目的:
- 为了研究由BINOL衍生而成的酸的结构,该酸的固态度有所变化.
- 评估这些BINOL酸盐物种的催化活性和不对称诱导.
- 了解不同的BINOL衍生物和反应条件如何影响催化物种的形成.
主要方法:
- 使用不同摩尔比率的BINOL和B(OPh) 的BINOL酸的合成3.
- 由此产生的酸盐物种的结构特征 (酸盐,酸盐,酸盐).
- 在不对称的阿齐里迪纳反应中对催化性能进行评估.
主要成果:
- 不同于之前的假设,BINOL可以形成酸盐和螺旋酸盐物种.
- 这些BINOL酸盐物种可以表现出催化活性,有时具有相反的不对称诱导.
- 3,3'-非替代的BINOL衍生物,特别是3,3'-Ph2BINOL,形成了不对称的亚齐里迪纳的有效酸催化剂.
结论:
- 由BINOL衍生的酸盐不是本质上劣质的催化剂;它们的结构和性能取决于反应条件和配体替代.
- 特定的酸盐结构 (酸盐,螺旋酸盐) 的形成决定了催化结果.
- 替代的BINOL连接物具有可调节的催化特性,在3,3'-位置要求固态的组可能会阻碍催化剂的形成.
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