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The mass spectra of 1,1-dimethyl-2,5-diphenyl-1-silacyclopentadiene, 1,1-dimethyl-2,5-diphenyl-1-silacyclopentane, 1,1-dimethyl-2,3,4,5-tetraphenyl-1-silacyclopentadiene and 1,1,4,4-tetramethyl-2,3,5,6-tetraphenyl-1,4-disila-2,5-cyclohexadiene were recorded using a 90° magnetic-sector type instrument. From the observed meta-stable peaks, most of the fragmentations giving rise to the more abundant ions have been assigned. For these compounds, up to 30% of the total intensity is carried by ions formed by some type of rearrangement. Specifically, four types of rearrangements are indicated and they involve the migration of: (1) hydrogen atoms from a phenyl group bonded to either an α- or β-carbon atom to the silicon atom of a siliconium ion; (2) a phenyl group from an α-carbon atom to a silicon atom;(3) a methyl group from one silicon atom to a second silicon atom in the 4-position; and (4) hydrogen atoms from silicon methyl groups to silicon with the simultaneous loss of CH 2 or C 2 H 4 .

The reaction of water with 2,3-bis(trifluoromethyl)-7,7-dimethyl-1,4-diphenyl-7-silanorbornadiene was investigated and found to give a benzyldimethylsilanol. The thermal elimination of dimethylsilylene was studied for five different 7-silanorbornadienes and the ease of elimination correlated to the substituents on the basal carbon atoms. In general, stability towards elimination is increased by bulky or electron withdrawing substituents. The reaction of dimethylsilylene with trichloro- and trifluoroborane was investigated and both were found to give dihalodimethylsilane instead of insertion products.

In this research, a comparison is drawn between unprogrammed reinforcement practices in a ward with token economy and in a control ward. The results clearly show that in unprogrammed interactions between staff and patients that are not formally part of the treatment, the aides of the token economy ward reinforce appropriate behaviors more than do those on the control ward.

In agreement with theoretical considerations and earlier experimental evidence, dipole moment measurements of selectively substituted o- and m-carborane derivatives established that in the polar icosahedra of o-B10H10C2H2 and m-B10H10C2H2 the carbon atoms and the borons adjacent to them constitute the positive pole. (Author)

The pyrolysis of diphenylsulphur di-imide gave azobenzene while di-t-butylsulphur di-imide pyrolysed to 2-methylpropene, ammonia, and hydrogen sulphide.