Strain Energies in Hydrocarbons from Heats of Combustion. II. Concerning the Possibility of a Transannular Interaction in 1,8-Cyclotetradecadiyne

Sublimation enthalpies at 298.15K using correlation gas chromatography and differential scanning calorimetry measurements

“…(5) and (6) [9]. A similar discrepancy has been noted for the value reported for cyclotetradecane [9,14,31]. The result of 78 550 J mol À1 (298.15 K) for azulene is in good agreement with two of the four values reported previously and suggest that the sublimation enthalpy is slightly larger than the value accepted for naphthalene.…”

“…A plot of ln(vapor pressure) against 1/T (K À1 ) resulted in Eqs. (5) and (6) [9]. A similar discrepancy has been noted for the value reported for cyclotetradecane [9,14,31].…”

“…Measurement of the sublimation enthalpy of 1,8-cyclotetradecadiyne has been repeated because of a large discrepancy observed between the value, calculated using Eqs. (1)±(3) (94 348 J mol À1 , Table 6) and the literature value of (166 000 J mol À1 , [9]). The sublimation enthalpy of azulene has been reported several times.…”

“…1,8-Cyclotetradecadiyne, purchased from K and K Laboratories was recrystallized from acetone, mp 96.7±97.38C ( [9]). The sample was assayed as 99.93% pure by gas chromatography on a 5 mÂ0.53 mm DB-1 Megabore capillary column.…”

“…tri-t-butylmethane acenaphthylene 58 600 [8] 57 820AE1110 Average of first 73 330 [18] 72 510AE1150 Average of all entries; 57 030 [16] two entries 73 000 [19] recommended value 7700 [17] 71 200 [20] azulene trans-stilbene 82 900 [20] 76 880AE1630 Average of second, 104 400 [26] 102 400AE1870 Average of top three entries; 78 550 b third and fourth entries 100 700 [27] recommended value 75 300 [21] 102 100 [28] 76 800 [19] 61 100 [29] 95 400 [25] 99 200 [19] naphthalene 1,8-cyclotetradecadiyne 72 600 [30] 72 600AE300 IUPAC 166 000 [9] 89 410AE1000 This work recommendation 89 410 b cyclotetradecane acenaphthene 98 520 [14] 92 170AE5500 Average of first, 86 940 [18] 85 310AE1580 Average of all entries; 134 950 [9] third and fourth entries 83 400 [33] recommended value 89 300 [31] 86 200 [34] 88 700 [32] 84 700 [35] diphenylacetylene triphenylmethane 95 100 [36] 95 100AE1100 First Entry 116 390 [39] 112 320AE5800 Average of top two entries 90 000 [37] 108 250 [40] 88 700 [38] 101 860 [41] fluorene c adamantane 81 500 [42] 86 130AE2170 Average of last 58 450 [47] 58 810AE2090 Average of all entries 80 200 [43] three entries 60 540 [48] recommended value 92 880 [44] 60 140 [49] 88 600 [18] 54 800 [50] 85 300 [46] 59 300 [51] 84 500 …”