Synthesis of a protonated C2-symmetric N,N-chiral “proton sponge”
摘要:
The hydrogen iodide salt of 1,8-bis-(N-benzyl-N-methylamino)naphthalene was synthesised as an 89/11 ratio of diastereomers in good yield. The structure of the major (+)-(RNRN/SNSN) diastereomer was determined by single crystal X-ray diffraction. The minor diastereomer is shown to be the meso-(RNSN) form by performing H-1 NMR n.O.e studies on isotopically desymmetrized 1-(N-benzyl-N-[C-13]-methylamino)-8-(N'-benzyl-N'-methylamino) naphthalene (HI salt). The half-life of interconversion of meso and dl forms is less than 2 minutes in CD2Cl2, at ambient temperature. (C) 1998 Elsevier Science Ltd. All rights reserved.