(E)- and (Z)-1-(Phenylsulfonyl)-4-(trimethylsilyl)-2-butenes:  Synthetic Equivalents for the 1-(1,3-Butadienyl) Anion and the 1,1-(1,3-Butadienyl) Dianion

Abstract

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

Synthetic methodologies for carbo-substituted conjugated dienes

“…373 A broader range of compounds of type 410 can be prepared on the basis of 1-phenylsulfo-4-trimethylsilylbut-2-ene (411) (pathway a). 374 The same products are formed when a more readily available isomer, 1-phenylsulfo-4-trimethylsilylbut-1-ene ( 412) is used instead (pathway b). 375 3.…”

Modern Synthetic Methods for the Stereoselective Construction of 1,3-Dienes

“…Among them, processes based on a vinylogous Peterson elimination reaction have been widely investigated [ 167 ]; in fact, quite a few natural products displaying the 1,3-dienic moiety have been prepared by the means of the addition of a γ-silyl-substituted allylmetal reagent to an aldehyde followed by a Peterson-type olefination protocol [ 168 ]. For this purpose, silylated allylboronates [ 169 ], allyltitanates [ 170 ], allyl sulfonates [ 171 ] and allylzirconium reagents [ 172 ] have been used, affording dienes in high E -selectivity. Despite their utility, these methodologies usually lack generality and require strict reaction conditions and/or the use of highly toxic reagents.…”

The 2-(Trimethylsilyl)ethyl Sulfur Group in Synthesis

“…(Figure 1). 50,52 Figure 1 50,52 The unsaturated silyl sulfones 73, 74 undergo efficient and stereospecific electrophilic conversion to their corresponding 1-substituted and 1,1-disubstituted silyl sulfones, for example 77. Thermal desilylation or treatment with fluoride ions or chromatography on silica gel of the products gives the corresponding 1-substituted and 1,1disubstituted 1,3-dienes, respectively, for example the diene 78 (Scheme 23).…”

“…Thermal desilylation or treatment with fluoride ions or chromatography on silica gel of the products gives the corresponding 1-substituted and 1,1disubstituted 1,3-dienes, respectively, for example the diene 78 (Scheme 23). 50 Therefore, silyl sulfones 73, 74 are useful equivalents for 1-(1,3-butanedienyl) anion or 1,1-(1,3-butanedienyl) dianion. This approach was used for…”