ABSTRACT
[reaction--see text] A simple and efficient method for the attachment of functionalized arene chromium carbonyls to a polymeric support has been developed. A highly efficient solid-phase synthesis of tertiary alcohols and esters was performed in a traceless manner using this strategy. The linker-fabrication protocol permits simultaneous immobilization of various substrates on the solid support.
Subject(s)
Chromium/chemistry , Combinatorial Chemistry Techniques , Organometallic Compounds/chemistry , Alcohols/chemical synthesis , Benzene Derivatives/chemistry , Chelating Agents/chemistry , Esters/chemical synthesis , Indicators and Reagents , Polystyrenes , Spectrophotometry, InfraredABSTRACT
[reaction: see text] A resin-based chromium catalyst for performing [6pi + 2pi] cycloaddition reactions has been prepared from chloromethylated polystyrene. The catalyst provides cycloadducts in yields comparable to the photochemical and thermal versions of these transformations, and the process is effective with a wide range of 6pi and 2pi reaction partners.
Subject(s)
Chromium/chemistry , Polystyrenes/chemistry , Catalysis , CyclizationABSTRACT
[reaction: see text] The Sceletium alkaloid mesembrine has been synthesized in 13% overall yield by a sequence featuring a [4 + 1] cycloaddition of a bis(alkylthio)carbene with a functionalized vinyl isocyanate.
Subject(s)
Alkaloids/chemistry , Indole Alkaloids , Alkaloids/chemical synthesis , Free Radicals/chemistry , Isocyanates/chemistry , Pyrrolidinones/chemical synthesis , Pyrrolidinones/chemistryABSTRACT
[formula: see text] Reaction of (eta 6-thiepin-1,1-dioxide)tricarbonylchromium(0) with excess terminal alkynes under photoactivation conditions affords novel pentacyclic adducts formally derived from a sequential [6 pi + 2 pi]/[6 pi + 2 pi]/[2 sigma + 2 pi] cycloaddition process.
