CO和CS键的激活由一个无效的1,4,2-diazaborole激活
Vignesh Pattathil1, Conor Pranckevicius1
1Department of Chemistry, Charles E. Fipke Centre for Innovative Research, University of British Columbia, Okanagan Campus, 3247 University Way, Kelowna, BC, Canada. conor.pranckevicius@ubc.ca.
Dalton transactions (Cambridge, England : 2003)
|April 23, 2025
概括
这项研究证明了通过涉及1,4,2-diazaboroles的 (3 + 2) 循环添加反应合成新型氧沙和 thiazaborole 衍生物. 机理学研究揭示了双极通路,解释了这些重要的异环化合物中观察到的反应性和选择性.
科学领域:
- 有机氧化物化学
- 异环化学 异环化学
- 有机合成 有机合成
背景情况:
- 1,4,2-diazaboroles是两性试剂,具有各种化学转换的潜力.
- 循环加法反应是构建复杂的异环框架的基础.
研究的目的:
- 为了合成新的1,3,2-oxazaborole和1,3,2-thiazaborole衍生物.
- 为了阐明1,4,2-diazaboroles与C=O和C=S键的反应机制.
- 为了研究与甲基伊索酸盐和二硫化碳反应中的区域选择性.
主要方法:
- 正式的 (3 + 2) 循环加法反应.
- 1,3,2-oxazaborole和1,3,2-thiazaborole衍生物的合成.
- 计算机理学研究 (密度函数理论).
主要成果:
- 成功合成了各种1,3,2-oxazaborole和1,3,2-thiazaborole化合物.
- 计算分析证实了协调的双极循环加法机制.
- 观察到对C=S的偏好,而不是C=N的添加,用甲基伊索酸盐,通过计算合理化.
- 从CS2双激活中形成一个螺旋环 bis ((1,3,2-thiazaborole).
结论:
- 1,4,2-diazaboroles是合成新型含异环的有效基石.
- 反应通过易斯酸激活的双极循环添加机制进行.
- 机械洞察力解释了观察到的反应模式和区域选择性.
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