Polyynes: Possible Bulk Synthesis and Chemical Properties - Polyynes: Synthesis, Properties, and Applications - page 433

FIGURE 18.10 Electronic absorption spectra recorded by the diode-array detector
of the HPLC. Top: C 10 ! R-CH ¼ CH-(C C) 3 -CH ¼ CH-R 0 or R-(CH ¼ CH) 2 -
(C C) 3 -R 0 . Middle: C 10 ! R-(CH ¼ CH) 2 -(C C) 2 -(CH ¼ CH)-R 0 . Bottom: C 12 ! R-
(CH ¼ CH) 3 -(C C) 3 -R 0 or R-(CH ¼ CH) 2 -(C C) 2 -(CH ¼ C) 2 -R 0 .

with a published spectrum of a compound having this moiety [1]. For the
compound with retention time 2.103min (again a C 8 ), whose spectrum is

reproduced in Figure 18.9 (middle) we have not found any reasonable match

with the reference spectra at our disposition. It appears that we are deal-
ing again with a chromophore relatively similar to that of the preceding