The discovery of novel chemical classes with novel modes of action for insect control form the backbone of innovation with the goal to deliver much-needed solutions into the hands of growers. Over the last decade, alkyl sulfones have emerged as one of the most versatile new classes and are under intensive investigation in many R&D programs in the industry, with Sumitomo Chemicals recently introducing oxazosulfyl as a first active ingredient to the market. In this review, we discuss some of our strategies to invent novel classes based upon ligand-based design, and also show how incorporation of physical chemical properties into our design enabled us to predictably control chewing and sucking pests.
View Article and Find Full Text PDFA synthesis of enantiopure 19-nor-Vitamin D(3) and its C-2 substituted cyclic phosphate analogs is achieved via in situ trapping of an α-sulfonyl anion with a CD-ring allyl chloride and 1,2-eliminative desulfonylation exploiting the basic properties of TBAF. The A-ring is prepared via anti-selective dithiane addition to vinyl sulfone and LiBH(4) mediated sequential bis reduction of an epoxy vinyl sulfone.
View Article and Find Full Text PDFAlcohol-directed intramolecular methylation of an enantiopure allyl sulfone using AlMe(3) provides a trans-hydrindane CD ring alcohol. The substrate cis-CD ring allyl sulfone alcohol is prepared via intramolecular allyl sulfonyl anion addition to aldehyde using Ba(OH)(2).
View Article and Find Full Text PDFA coupling strategy for the synthesis of 2,4-dimethyl-1α,25(OH)(2)D(3) is achieved which involves methylation of a pro-A ring vinyl sulfone and in situ traping of the allyl sulfonyl anion with a CD ring allyl chloride. TBAF-promoted 1,2-eliminative desulfonylation and concomitant silyl ether deprotection gives the vitamin D(3) analogue.
View Article and Find Full Text PDFDimethylsulfonium methylide undergoes S(N)2' addition/1,2-elimination with epoxy vinyl sulfones to generate enantiopure six and seven membered cross-conjugated hydroxy vinyl sulfones. Moderate to excellent yields were obtained for both six and seven membered substrates.
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