Synthesis, Isolation, and Equilibration of 1,9- and 7,8-C ₇₀ H ₂

Abstract

Equilibration of 1,9- and 7,8-C(70)H(2) has allowed the relative free energy of these isomers to be measured. These "simplest hydrocarbon derivatives of C(70)" are formed by hydroboration of C(70) at room temperature. Analysis of the platinum-catalyzed equilibration of these isomers yielded a relative free energy at 295 kelvin of 1.4 +/- 0.2 kilocalories per mole, with the 1,9 isomer being more stable. This value is in excellent agreement with the ab initio HF/6-31 G(*) calculated energy difference of 1.3 kilocalories per mole, whereas semiempirical calculations gave poor agreement.

Highly Regio‐ and Stereoselective [2+3] Cycloadditions of Azomethine Ylides to [70]Fullerene

“…[13] The UV/Vis spectra of 1 and 2 were very similar to the spectra of other known C 70 -based compounds with an 8,25-addition pattern. [13] Therefore, it is very reasonable that 1 and 2 should also be considered as 8,25-addition products because the 8,25-bond is the most reactive one in the [70]fullerene cage.…”

“…7.66 (dt,J = 7.8,1.6 Hz,1 H),7.96 (d,J = 7.8 Hz,1 H),8.03 (dt,J = 7.6,1.6 Hz,1 H),8.61 (d,J = 4.6 Hz,1 H),8.88 (d,J = 4.6 Hz,1 H) ppm. 13 C NMR [150 MHz; CS 2 /(CD 3 ) 2 CO, 9:1]: δ = 72. 17, 73.97, 76.18, 78.97, 123.10, 124.37, 128.43, 130.82, 131.13, 131.16, 131.20, 131.26, 131.47, 132.97, 133.50, 133.60, 133.80, 136.03, 136.52, 137.25, 137.52, 140.23, 140.33, 140.44, 140.48, 142.68, 142.88, 143.02, 143.09, 143.23, 143.32, 143.48, 143.52, 144.90, 145.33, 145.74, 145.78, 146.04, 146.25, 146.37, 146.84, 147.00, 147.06, 147.11, 147.18, 147.34, 147.41, 147.45, 147.55, 148.01, 148.71, 148.87, 148.89, 148.97, 149.09, 149.14, 149.26, 149.50, 149.63, 149.65, 149.72, 149.74, 149.77, 150.08, 150.16, 150.44, 150.48, 150.51, 150.55, 150.61, 150.64, 150.70, 150.83, 151.14, 151.28, 151.43, 151.54, 154.94, 155.83, 156.21, 156.25, 160.39 131.24, 131.28, 131.31, 131.35, 131.68, 133.12, 133.40, 133.54, 133.65, 133.88, 134.04, 135.19, 135.84, 137.43, 137.88, 138.44, 140.18, 140.59, 140.84, 141.27, 142.91, 143.06, 143.31, 143.39, 143.47, 144.26, 145.64, 145.85, 145.95, 146.19, 146.24, 146.43, 146.91, 147.00, 147.01, 147.14, 147.44, 147.50, 147.63, 148.67, 148.85, 148.98, 149.10, 149.16, 149.20, 149.23, 149.25, 149.34, 149.69, 149.81, 149.88, 149.93, 150.01, 150.17, 150.31, 150.47, 150.53, 150.54, 150.62, 150.67, 150.76, 150.78, 150.96, 151.28, 151.30, 151.36, 151.47, 154.94, 155.17, 155.96, 158.26 19, 66.57, 67.67, 72.68, 76.63, 122.89, 123.06, 123.45, 123.63, 124.39, 124.73, 124.93, 125.55, 127.84, 128.42, 129.14, 130.64, 131.18, 131.23, 131.30, 131.73, 132.97, 133.10, 133.43, 133.70, 133.79, 135.34, 136.19, 136.35, 136.50, 137.40, 137.44, 138.64, 140.37, 140.73, 142.82, 142.87, 143.15, 143.19, 143.24, 143.34, 145.69, 145.79, 146.04, 146.25, 146.40, 146.83, 147.04, 147.09, 147.33, 147.45, 147.51, 148.79, 148.89, 148.97, 149.06, 149.11, 149.26, 149.42, 149.57, 149.69, 149.91, 150.06, 150.45, 150.53, 150.63, 150.72, 151.00, 151.37, 151.42, 151.48, 155.15, 157.22, 159.06, 159.24, 159.76 Supporting Information (see footnote on the first page of this article): NMR spectra of 1 and 2 and UV/V...…”

Reaction of [70]Fullerene with Tetraethyl Methylenediphosphonate or Diethyl (Cyanomethyl)phosphonate Revisited

“…[4][5][6][7] In 1994, Meier et al noted the similarity of the UV/Vis spectra of the C1-C2 and C5-C6 isomers of their synthesized C 70 isoxazoline derivatives [5a] to those of C 70 H 2 . [11] Their further investigations indicated that C1-C2 isomers bearing different addends gave rise to similar UV/Vis spectral profiles.…”

Hydrogenation of Fullerene C60: Material Design of Organic Semiconductors by Computation

“…In Figure 5 (b), the second H 2 pair is added to one of the carbon atom pairs labeled 1-8 and these isomers are named 1-8. Experimentally, some of the eight isomers have been synthesized, and four isomers (1, 4, 6,and8)amongthem were identified [36,[39][40][41][55][56][57].…”

“…Hydrogenated fullerenes, C 60 H 2 ,C 60 H 4 ,a n dC 60 H 6 , have been prepared by hydroboration [35,36], hydrozirconation [37], rhodium-catalyzed hydrogenation [38], diimide [39] and hydrazine [40] reduction, dissolving metal reduction [41,42], photoinduced-electron-transfer reduction with 10-methyl-9,10-dihydroacridine [43,44], and ultrasonic irradiation in decahydronaphthalene [45]. In many cases, a mixture of C 60 ,C 60 H 2 ,a n dC 60 H n (n > 2) is obtained [46].…”