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The electron spin resonance spectrum of the perinaphthene f r e e r a dical i s reported and a discussion of electron spin density in this r a d i c a l i s given.

Tile synthesis of optically active crown ethers (8), (1 4), and (1 8 ) incorporating helicene molecular frameworks is reported. Their chiral recognition properties have been examined and show that (M)-(-)-( 14), although of the same helicity as ( M ) -( -) -( 8) and ( M ) -( -) -( 1 8 ) , exhibits opposite chiral recognition for the transport of methyl phenylglycinate, 1 -phenylethylamine, and 1,2diphenylethylamine, and that the pentahelicene crown (8) has a higher enantiomer selectivity than the hexahelicene crown (14) and hexa[7]circulene crown (18) towards these substrates. At 6.0-6.2% transport using (8), the optical purity of methyl phenylglycinate and 12-diphenylethylamine was as high as 7 7 4 2 % .Paper 9/0 1360A

2,3 : 6,7-Dibenzobicyclo[3.3.1]nona-2,6-diene-4,8-diol was synthesized and resolved via (−)-menthoxyacetate. Several kinds of optically active derivatives with the same absolute configuration were prepared from the (−)-diol and their chiroptical properties were recorded. The absolute configuration of this series of compounds was determined to be 1R, 5R by a chemical correlation with (R)-(−)-3-phenylbutanoic acid via (−)-1,3-diphenylglutaric acid and (−)-2,4-diphenylpentane.