28995-90-6Relevant articles and documents
Hypervalent iodine in synthesis: 9. A new, effective synthesis of acetylenic sulfones
Liu,Chen
, p. 1997 - 2003 (1992)
Alkynylphenyliodonium salts can easily react with sodium sulfinates under PTC conditions at room temperature to afford a convenient, effective method for the preparation of acetylenic sulfones.
Preparation of resin-bound alkynyl iodonium salts and their application in organic synthesis as alkynyl transfer reagents
Huang, Xian,Zhu, Qing
, p. 6373 - 6375 (2007/10/03)
We have synthesized polymer-supported alkynylphenyl iodonium salts. They served as effective alkynyl transfer reagents for the preparation of acetylenic sulfones; the by-product, polymer supported (4-iodostyrene), could be reactivated for reuse numerous t
THE ELECTRON SPIN RESONANCE SPECTRA OF THE ANNULENE (CYCLOBUTADIENE) RADICAL CATIONS, R4C4+.
Courtneidge, John L.,Davies, Alwyn G.,Lusztyk, Ewa,Lusztyk, Janusz
, p. 155 - 164 (2007/10/02)
A series of simple (R=R') and mixed (RR') cyclobutadiene radical cations, R2R'2C4+., have been prepared by photolysis of the alkynes, RCCR' or of mixtures of the alkynes RCCR and R'CCR', in dichloromethane in the presence of aluminium chloride, and the e.s.r. spectra have been recorded.The magnitude of the 13C hyperfine coupling in Et4C4+. confirms that it is a ?-radical, with no evidence for out-of-plane or in-plane (Jahn-Teller) distortion.The values of a(Hβ) for the radicals (RCH2)4C4+. and (RCH2)2R'2C4+. indicate that, as the bulk of the alkyl substituents increases, the group R is pushed out of the plane of the ring.Some unusual temperature effects on a(Hβ) are ascribed to interaction of the radical cation with the solvent or with the counterion.As the bulk of the alkyl groups increases, the g-value decreases from 2.0030 to about 2.0022. cis- and trans-Isomers of the radicals Me2tBu2C4+., Et2tBu2C4+., iBu2tBu2C4+., and propably Me2Et2C4+. have been identified, and the spectra of cis- and trans-Me2tBu2C+. are analysed in terms of breaking of the degeneracy of the molecular orbitals of the cyclobutadiene system by differential electron release by the alkyl groups (tBu > Me).