CRYSTAL-STRUCTURE AND CIRCULAR-DICHROISM OF (1R,3R,4R), (1R,3R,4R)-(BORNANE 2-ONE,3-YL)-3 BORNANE 2-ONE (DICAMPHOR)

(+)-Camphor reacts in basic media, with N-sulfinylaniline to give, in good yields, dicamphoquinone, which is hydrogenated to dicamphor. Crys tals of dicamphor (C20H30O2) belong to space group P2(1), with a = 6.9 20(1) angstrom, b = 11.207(1) angstrom, c = 11.516(1) angstrom, beta = 99.62(1)0, z = 2, T = 293 K. The final R is 0.044 for 1113 observed r eflections. The cohesion of the crystal is the result of van der Waals interactions. The two camphor moieties in this 1.4-diketone are locat ed in chiral positions with respect to each other. The two carbonyl gr oups form a right handed helix.The Circular Dicroism (CD) spectrum exh ibits two Cotton effects of opposite sign and equal intensities in the region of n --> pi transition: positive at longer wavelength and neg ative at shorter wavelength. The nature of CD is discussed.