重要主族元素的多个化合物的发展，新的化学.pdfVIP

中国试剂网 2 . 3 . 2 . 3 1 TCIMAILnumber 105 Contribution The development of new chemistry on multiple-bond compounds with heavier main group elements Renji Okazaki, Professor, Faculty of Science, Japan Women’s University 1. Introduction The multiple-bond compounds including second period elements such as olefin, imine (Schiff base), ketone, acetylene, nitrile etc. are stable compounds and play a very important role in organic chemistry. Contrary to this, multiple-bond compounds containing elements from the third period onward (named as heavier main group elements), have long bond distances and their π bond energy generated through the overlapping of p-orbitals is low so that they are extremely unstable. Examples of π bond energy are shown in Table 1.1 C=C 65 N=N 60 C=O 77 C=Si 38 P=N 44 C=S 52 Si=Si 25 P=P 34 Si=S 50 Table 1. π bond energy associated with double-bond including the multiple-bond of heavier main group elements. (kcal mol-1) [MP4/EXT//3-21G(d)] Due to suc