Acta Phys. -Chim. Sin. ›› 2012, Vol. 28 ›› Issue (08): 1849-1853.doi: 10.3866/PKU.WHXB201206081

• THEORETICAL AND COMPUTATIONAL CHEMISTRY • Previous Articles     Next Articles

Selectivity of [2+2] C=O Cycloaddition and α-H Cleavage of Carbonyl Compounds on Si(100) Surface

ZHANG Ji-Chao1, CHENG Xue-Li2, CHENG Yu-Qiao1, MENG Xiang-Hua1, LIU Yong-Jun2, LIU Cheng-Bu2   

  1. 1. Geological Scientific Research Institute, Shengli Oilfield Company of SINOPEC, Dongying 257015, Shandong Province, P. R. China;
    2. School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, P. R. China
  • Received:2012-04-01 Revised:2012-06-08 Published:2012-07-10
  • Contact: LIU Yong-Jun E-mail:yongjunliu_1@sdu.edu.cn
  • Supported by:

    The project was supported by the Natural Science Foundation of China (21173129).

Abstract:

Recent studies have demonstrated that a simple ketone [acetone, (CH3)2C=O)] reacts with the Si(100) surface in a [2+2] C=O cycloaddition or by α-H cleavage to form Si―C and/or Si―O σ-bonds. To understand the reactivity of carbonyl compounds bearing different substitutes, the [2 + 2] C=O cycloaddition and α-H cleavage of carbonyl compounds CH3COR (R=CH3, H, C2H5, C6H5) on Si(100) surface have been investigated using density functional theory at the B3LYP/6-311 ++ G(d,p)//6-31G(d) level. Our calculation results reveal that: (1) both cycloaddition and α-H cleavage corresponds to very low energy barriers (lower than 25 kJ·mol-1), and the energy barrier for cycloaddition is slightly higher than α-H cleavage; (2) the substituents on the carbonyl compound [CH3COR] has only a minor influence on the energy barrier; (3) the α-H cleavage reactions are thermodynamically and kinetically more favorable than cycloadditions; (4) for the α-H cleavage of butanone, reactions at C1 and C3 positions are competitive. These findings suggest that the reactions of ketone derivatives with Si(100) surface will generate multiple products.

Key words: Clycloaddition, α-H cleavage, Carbonyl compound, Density functional theory

MSC2000: 

  • O641