Ring-Opening Cyclization of Spirocyclopropanes Using Sulfoxonium Ylides
نویسندگان
چکیده
منابع مشابه
Synthesis of fused cyanopyrroles and spirocyclopropanes via addition of N-ylides to chalconimines.
Addition of N-ylides derived from DABCO to chalconimines takes place through a Michael addition-cyclization pathway to afford fused cyanopyrroles and/or spirocyclopropanes. The product profile depends heavily on the nature of chalconimines. While 6-membered cyclic chalconimines provide a mixture of pyrrole and spirocyclopropane, 5-membered chalconimines furnish exclusively spirocyclopropane. Cy...
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Strained azirinium ylides derived from 2H-azirines and α-diazoketones under Rh(II)-catalysis can undergo either irreversible ring opening across the N-C2 bond to 2-azabuta-1,3-dienes that further cyclize to 2H-1,4-oxazines or reversibly undergo a 1,5-cyclization to dihydroazireno[2,1-b]oxazoles. Dihydroazireno[2,1-b]oxazoles derived from 3-aryl-2H-azirines and 3-diazoacetylacetone or ethyl diaz...
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Polydimethylsiloxane (PDMS) has been synthesized by ring-opening polymerization of octamethylcyclotetrasiloxane (D4) in microemulsion with acidic catalyst. The structure and properties of microemulsion were characterized by Transmission Electron Microscopy (TEM), Fourier Transform Infrared Spectroscopy (FT-IR), Photo Correlation Spectroscopy (PCS). The effect of the variation in pH value, amoun...
متن کامل3-Pyridylnitrene, 2- and 4-pyrimidinylcarbenes, 3-quinolylnitrenes, and 4-quinazolinylcarbenes. Interconversion, ring expansion to diazacycloheptatetraenes, ring opening to nitrile ylides, and ring contraction to cyanopyrroles and cyanoindoles
Precursors of 3-pyridylnitrene and 2- and 4-pyrimidinylcarbenes all afford mixtures of 2- and 3-cyanopyrroles on flash vacuum thermolysis, but 3-cyanopyrroles are the first-formed products. 3-Quinolylnitrenes and 4-quinazolinylcarbenes similarly afford 3-cyanoindoles. 2-Pyrimidinylcarbenes rearrange to 3-pyridylnitrenes, but 4-pyrimidinylcarbenes and 4-quinazolinylcarbenes do not necessarily re...
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ژورنال
عنوان ژورنال: Chemical and Pharmaceutical Bulletin
سال: 2020
ISSN: 0009-2363,1347-5223
DOI: 10.1248/cpb.c20-00132