Synthedses of Aklylsilanes and Study of the Ion-Molecule Reactions Related to their Properties

Research Project

Project/Area Number	01550653
Research Category	Grant-in-Aid for General Scientific Research (C)
Allocation Type	Single-year Grants
Research Field	有機工業化学
Research Institution	Nara Women's University
Principal Investigator	YAMAMOTO Masao Nara Women's University, Dep. of Chemistry Professor, 理学部, 教授 (80028159)
Co-Investigator(Kenkyū-buntansha)	TAKEUCHI Takae Nara Women's University, Dep. of Chemistry Assistant, 理学部, 助手 (80201606) IWAI Kaoru Nara Women's University, Dep. of Chemistry Associate Professor, 理学部, 助教授 (90127423)
Project Period (FY)	1989 – 1990
Project Status	Completed (Fiscal Year 1990)
Budget Amount *help	¥1,700,000 (Direct Cost: ¥1,700,000) Fiscal Year 1990: ¥100,000 (Direct Cost: ¥100,000) Fiscal Year 1989: ¥1,600,000 (Direct Cost: ¥1,600,000)
Keywords	Alkylsilanes / EIMS / Ion-Molecule Reaction / LC / MS / マヌスペクトル
Research Abstract	The alkylmonosilanes, alkyldisilanes and their deuterium labeled compounds were synthesized, and the EIMS were measured. The fragmentation mechanisms were studied in the comparison with their condensed phase reactions. Most of the fragment ions appeared in EIMS can be explained on the analogy of the condensed phase reactions. The main ion of m/z 73 (CH_3SiH_2CH_2CH_2^+) in monolanes is stabilized by s-p conjugation. From the abinitio MO calculation, the optimized geometry of this ion shows that the SiH_2-CH_2 bond and the neighboring CH_2-CH_2 bond become shorter than those of molecular ion and the bond angle of Si-C-C approaches to right angles. The characteristic ion of 1, 1, 2, 2-tetramethyldisilane is also m/z 73 as same as that of monosilanes. However, from the results of deuterium labeled compounds it can be known that the structure of this ion, (CH_3)_3Si^+, is quite different from that of monosilanes. The intermediate of this decomposition reaction is considered to be the four-membered ring structure. The mass spectra of dimethylphenylchlorosilane (MW=170) were measured by LC/MS method. Two kinds of the eluates, CH_3CN and MeOH/AcONH_4, were used. From the results of ion-molecule reaction between sample and eluate, it may become possible to investigate the properties and reactivities of the sample molecule. As the difference between both eluates it can be found that the intensity ratio between m/z 170 and m/z 171 of molecular ion group is different.