156927-34-3Relevant articles and documents
Ring-Chain Tautomerism And Crystal Structure Of Some 1,3-Oxazacyclanes, And The Electrophilic Substituent Constants For Some Heteroaryl Groups In Solution And In The Gas-Phase
Fulop, Ferenc,Sillanpaeae, Reijo,Dahlqvist, Martti,Pihlaja, Kalevi,Vainiotalo, Pirjo
, p. 1093 - 1108 (2007/10/02)
In principle, the ring-chain tautomeric ratios of a number of 2-heteroaryl-substituted oxazolidines and tetrahydro-1,3-oxazines are well suited for determination of the Hammett-Brown ?+ constants of heteroaryl substituents such as 2-furyl, 3-furyl, 3-thienyl and 2-pyrrolyl in CDCl3 solution and in the gas phase.However, a number of factors, and especially hydrogen-bonding, can change the monomeric character of either the ring or the chain form (or both), leading to deviations from the ideal ?+ values.X-Ray analysis has demonstrated the chain structures of theproducts of the reactions of L-(-)-norpseudoephedrine and (+/-)-trans-2-aminomethylcyclohexanol with pyrrole-2-carboxaldehyde.
RING-CHAIN TAUTOMERISM OF 1,3-OXAZOLIDINES PREPARED FROM NOREPHEDRINE AND NORPSEUDOEPHEDRINE
Fulop, Ferenc,Bernath, Gabor,Mattinen, Jorma,Pihlaja, Kalevi
, p. 4317 - 4324 (2007/10/02)
The reactions of norephedrine and norpseudoephedrine with eleven different arometic aldehydes led, in each case, to tautomeric equilibria consisting of two ring and one open-chain forms and obeying the equation: log KX = p?+ + c, whe