Department of Chemistry and Biochemistry, Florida State University, Tallahassee, FL 32306, USA.
Science. 2010 Nov 19;330(6007):1047; author reply 1047. doi: 10.1126/science.1196188.
Legrand et al. (Reports, 16 July 2010, p. 299) reported the experimental observation of square-planar and rectangular-bent geometries of 1,3-dimethylcyclobutadiene (Me(2)CBD) confined within a crystalline matrix. However, we found no evidence for the Me(2)CBD formation. We argue that the experimental x-ray density data are better attributed to the bicyclic β-lactone intermediate where carbon dioxide is covalently bound to cyclobutadiene.
勒格朗等人（报告，2010 年 7 月 16 日，第 299 页）报道了在晶体基质中受限的 1,3-二甲基环丁二烯（Me（2）CBD）的平面正方形和矩形弯曲几何形状的实验观察。然而，我们没有发现 Me（2）CBD 形成的证据。我们认为，实验 X 射线密度数据更归因于双环β-内酰胺中间体，其中二氧化碳与环丁二烯共价结合。
