A Palladium-Catalyzed Regio- and Stereoselective Four-Component Coupling Reaction
作者:Daniel J. Knapton、Tara Y. Meyer
DOI:10.1021/jo0484068
日期:2005.2.1
Pd(PPh3)4 catalytically assembles sulfenamide, alkyne, carbon monoxide, and diphenyl diselenide regio- and stereoselectively in a one-pot four-componentcoupling reaction to yield (Z)-β-selenyl acrylamides. The reaction proceeds in good to excellent yields (60−95%) and is tolerant of a range of functional groups on both the nitrogen of the sulfenamide and the alkyne. Moderate selectivities ranging
In the reaction of N-methylbenzenesulfenamide (1) with thioanisole (4) in the presence of trifluoroaceticacid (TFA), the initial rate υ0 of total appearance of 2- and 4-(methylthio)phenylphenyl sulfides (5) is first and zero order with respect to the initial concentrations of 1 and 4, respectively: υ0=kobs[1]0. The pseudo-first order rate constant kobs is evaluated as 5.2×10-4 sec-1 with varying
A composition comprising an oil of lubricating viscosity and a compound represented by formula (I) wherein: x is 0 or 1; R1 is a hydrocarbyl group containing about 4 or about 18 carbon atoms; R2 is an aliphatic hydrocarbyl group containing about 1 to about 12 carbon atoms; and y is 0 or 1, which composition is effective at swelling seals.
An object of the present invention is to provide a golf ball having excellent resilience performance. The present invention provides a golf ball comprising a constituent member, wherein at least a part of the constituent member is formed from a rubber composition containing (a) a base rubber, (b) a co-crosslinking agent, (c) a crosslinking initiator, and (d) an organic sulfur compound, wherein (d) the organic sulfur compound contains at least one member selected from the group consisting of a thiophenol having a halogenated sulfanyl group, a metal salt of a thiophenol having a halogenated sulfanyl group, and a diphenyl disulfide having a halogenated sulfanyl group.
Experimental and Computational Evidence for the Formation of Iminopersulfinic Acids
作者:Edward L. Clennan、Ming-Fang Chen、Alexander Greer、Frank Jensen
DOI:10.1021/jo9800208
日期:1998.5.1
An experimental and computational study of the reactions of singlet oxygen with N-substituted sulfenamides is reported. Intermediates capable of epoxidizing norbornene were observed during the photooxidations of three sulfenamides. These results are used to argue for formation of iminopersulfinic acids. The structural integrity of two iminopersulfinic acids was supported by their successful location at the MP2/6-31G* level of theory. Furthermore, the inability to locate computationally significant persulfinimide precursors suggests that the iminopersulfinic acids form by enelike reactions involving near-simultaneous addition of singlet oxygen to sulfur and hydrogen abstraction.