TY - JOUR
T1 - The Preparation and Absolute Configurations of Enantiomerically Pure C4-Symmetric Tetraalkoxyresorcin[4]arenes Obtained from Camphorsulfonate Derivatives
AU - Buckley, B.R.
AU - Bulman Page, P.C.
AU - Chan, Y.
AU - Heaney, H.
AU - Klaes, M.
AU - Mcildowie, M.J.
AU - Mckee, V.
AU - Mattay, J.
AU - Mocerino, M.
AU - Moreno, E.
AU - Skelton, Brian
AU - White, Allan
PY - 2006
Y1 - 2006
N2 - The preparation of a series of diastereoisomeric tetracamphorsulfonates derived from racemic tetramethoxyresorcin[4]arenes was achieved by reactions with an excess of (S)(+)-10-camphorsulfonyl chloride in pyridine followed by isolation using flash chromatography. Tetradeprotonation of a number of tetramethoxyresorcin[4]arenes using n-butyllithium in tetrahydrofuran, followed by reactions using (S)-(+)10-camphorsulfonyl chloride, gave the same tetracamphorsulfonates. Mono-, di- and tricamphorsulfonates were also prepared following selective deprotonation. In the reactions with tetraisopropyloxy- and tetracyclopentyloxyresorcin[4]arenes, only the mono- and dicamphorsulfonates were formed. X-ray crystallographic analysis established the absolute configurations of three diastereoisomerically pure tetracamphorsulfonates, including a diastereoisomer prepared from 6,12,18,24-tetramethoxy-2,8,14,20-tetrakis(2-methylpropyl)resorcin[4]arene. An additional pair of diastereoisomers was also prepared using (R)-(-)-10-camphorsulfonyl chloride and 6,12,18,24-tetramethoxy-2,8,14,20-tetrakis(2-methylpropyl)resorcin[4]arene, for one of which the structure was confirmed by an additional X-ray structure determination. Hydrolytic removal of the camphorsulfonyl residue(s) from the various diastereoisomers gave enantiomers of known absolute configurations. In some cases, the chiral nonracemic tetraalkoxyresorcin[4]arenes were converted into known tetrabenzoxazine derivatives by using N,N-bis(methoxymethyl)[(S)-(-)-(a-methylbenzyl)]amine in thermal or microwave - assisted reactions. (c) Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006.
AB - The preparation of a series of diastereoisomeric tetracamphorsulfonates derived from racemic tetramethoxyresorcin[4]arenes was achieved by reactions with an excess of (S)(+)-10-camphorsulfonyl chloride in pyridine followed by isolation using flash chromatography. Tetradeprotonation of a number of tetramethoxyresorcin[4]arenes using n-butyllithium in tetrahydrofuran, followed by reactions using (S)-(+)10-camphorsulfonyl chloride, gave the same tetracamphorsulfonates. Mono-, di- and tricamphorsulfonates were also prepared following selective deprotonation. In the reactions with tetraisopropyloxy- and tetracyclopentyloxyresorcin[4]arenes, only the mono- and dicamphorsulfonates were formed. X-ray crystallographic analysis established the absolute configurations of three diastereoisomerically pure tetracamphorsulfonates, including a diastereoisomer prepared from 6,12,18,24-tetramethoxy-2,8,14,20-tetrakis(2-methylpropyl)resorcin[4]arene. An additional pair of diastereoisomers was also prepared using (R)-(-)-10-camphorsulfonyl chloride and 6,12,18,24-tetramethoxy-2,8,14,20-tetrakis(2-methylpropyl)resorcin[4]arene, for one of which the structure was confirmed by an additional X-ray structure determination. Hydrolytic removal of the camphorsulfonyl residue(s) from the various diastereoisomers gave enantiomers of known absolute configurations. In some cases, the chiral nonracemic tetraalkoxyresorcin[4]arenes were converted into known tetrabenzoxazine derivatives by using N,N-bis(methoxymethyl)[(S)-(-)-(a-methylbenzyl)]amine in thermal or microwave - assisted reactions. (c) Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006.
U2 - 10.1002/ejoc.200600591
DO - 10.1002/ejoc.200600591
M3 - Article
VL - 2006
SP - 5135
EP - 5151
JO - European Journal of Organic Chemistry
JF - European Journal of Organic Chemistry
SN - 1099-0690
IS - 22
ER -