Hu Shaowei, Shima Takanori, Hou Zhaomin
Organometallic Chemistry Laboratory, RIKEN Cluster for Pioneering Research, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan.
Advanced Catalysis Research Group, RIKEN Center for Sustainable Resource Science, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan.
J Am Chem Soc. 2020 Nov 25;142(47):19889-19894. doi: 10.1021/jacs.0c10403. Epub 2020 Nov 10.
The reductive coupling of carbon monoxide (CO) by metal hydrides is of fundamental interest and practical importance. Herein we report an unprecedented hydrodeoxygenative cyclotetramerization of CO by a trinuclear titanium polyhydride complex (CMeSiMe)Ti(μ-H) (). The reaction of CO with at -78 °C gave an ethen-1,2-diyl species [CH═CH] through the hydrodeoxygenative dimerization of two molecules of CO, which upon cycloaddition to another two molecules of CO afforded a cyclobuten-3,4-diyl-1,2-diolate unit [CHO]. The hydrogenolysis of the [CHO] species with H yielded a tetrahydrocyclobuten-1,2-diolate species [CHO], which on heating at 100 °C gave a cyclobuten-2-yl-1-olate product [CHO]. The acidolysis of the [CHO] and [CHO] species with HCl afforded γ-butyrolactone and cyclobutanone, respectively.
金属氢化物对一氧化碳（CO）的还原偶联反应具有重要的基础研究意义和实际应用价值。在此，我们报道了一种前所未有的由三核钛多氢配合物(CMeSiMe)Ti(μ-H)（）实现的CO加氢脱氧环四聚反应。在-78°C下，CO与该配合物反应，通过两个CO分子的加氢脱氧二聚反应生成了乙烯-1,2-二基物种[CH═CH]，该物种与另外两个CO分子进行环加成反应，得到了环丁烯-3,4-二基-1,2-二醇酸酯单元[CHO]。用H对[CHO]物种进行氢解反应，生成了四氢环丁烯-1,2-二醇酸酯物种[CHO]，该物种在100°C加热时得到了环丁烯-2-基-1-醇酸酯产物[CHO]。用HCl对[CHO]和[CHO]物种进行酸解反应，分别得到了γ-丁内酯和环丁酮。
