Langmuir 1994,10, 1633
1633
A d d it ions and Corrections Two-Dimensional Rotational Dynamic Chirality and a Chirality Scale
Y. Hel-Or, S. Preleg, and D. Avnir Langmuir 1990, 6, 1691. The 2 values in Table I are in error (due to incorrect normalization) and should read as in the corrected Table I below. 2 values in the Discussion should be replaced accordingly. The contents and the conclusions are not altered by this correction. Parts A and C of Figure 4 are S, and R,, respectively. Table I. The Two-DimensionalChirality 2 Values for Various Alkane Skeletons
No." 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25
alkaneb propane (R)-n-butane (S)-n-butan'e n-pentane n-hexane n-heptane n-octane n-nonane n-decane n-pentane (c) n-decane ( c ) ~ 2-methylbutane 3-ethylpentane 2-methylhexane 3-methylhexane 3-methylhexane (c) 2,3-dimethylhexane 2,4-dimethylhexane 2,3,4-trimethylhexane
2,3,4,5-tetramethylhexane 2-methyldecane 2,9-dimethyldecane 2,4,7,9-tetramethyldecane
2,3,4,7,8,9-hexamethyldecane 2,3,4,5,6,7,8,9-octamethyldecane
Z valueC +0.047 331d +0.987 196 -0,975 416 +0.028 706 +0.356 431 +0.020 279 +0.353 314 +0.015 634 +0.216 031 -0,701 432 -0.085 241 -0.475 753 -0.964 701 -0.064 801 +0.433 112 +0.119 801 -0,007 465 +0.057 788 +0.138 099 -0.163 714 -0.103 529 -0.347 506 -0,454 714 -0,137 505 -0,088666
"The numbers refer to the structures in Figure 1. bunless indicated, the most stable conformer is taken, usually the all-trans. "c" means at least one cis angle (seeFigure 1). The error bars decrease with the size of the object. Thus, for propane (1)it is 10.05, for n-pentane (4) it is 10.03, and for the n-nonane (8) it is 10.02. See Figure 6. The Z values there are (a) -0.058, (b) -0.058, (c) 0.95, and (d) -0.95. e This is the farnesol skeleton (a sesquiterpene).
0743-7463/94/2410-1633$04.50/00 1994 American Chemical Society
