Bis(diisopropylamino)silylene and its dimer [8]

Journal of the American Chemical Society

Volumn 120, Issue 38, 1998, Pages 9955-9956

  Tsutsui, S ^a   Sakamoto, K ^a   Kira, M ^a  

^a TOHOKU UNIVERSITY   (Japan)

Author keywords

[No Author keywords available]

Indexed keywords

BIS(DIISOPROPYLAMINO)SILYLENE; DIMER; HEXANE; SILANE DERIVATIVE; SILICON; TOLUENE; UNCLASSIFIED DRUG;

CHEMICAL STRUCTURE; LETTER; NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY; PHOTOCHEMISTRY; TEMPERATURE DEPENDENCE; ULTRAVIOLET SPECTROSCOPY;

EID: 0032581952     PISSN: 00027863     EISSN: None     Source Type: Journal    
DOI: 10.1021/ja980008x     Document Type: Letter

References (51)

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31. A reviewer has pointed out the possibility that the new species observed by 'H NMR is an oligomer of 1 such as the cyclic trimer, lO-PriNhSilj, which is invisible in the UV spectra. The possibility will be rationalized if the cyclotrisilane is in equilibrium with a small amount of 1 (the ratio of the trimer with 1 > 95/5); a cyclotrisilane has been known to decompose at 40 °C to give the corresponding silylene and disilene.12 However, a UV-vis spectrum obtained after exhaustive photolysis of 2 (5.0 x 10 4 M) in 3-MP at room temperature showed that the absorbance of the band due to 1 was 0.50. The result means that the absorption coefficient of 1 should be at least 18 000, if the yield of 1 is less than 5%. The estimated e value is far larger than that expected for a forbidden n — p transition of a silylene. On the other hand, according to our assignment, the e value of 1 is estimated reasonably as >950.
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51. Sakamoto, K.; Tsutsui, S.; Kira, M., unpublished results. l,l-Bis(diethylamino)dimethyldisilene was generated by the photolysis of the corresponding 1-phenyl-7,8-disilabicyclo-[2.2.2]octa-2,5-dienes in 3-MP matrix at 77 K. Experimental details are given in the Supporting Information.