A high-level ab initio and density functional investigation of cyclopropenyl anion and its mono-, di-, and trisubstituted derivatives

Journal of the American Chemical Society

Volumn 119, Issue 50, 1997, Pages 12322-12337

  Merrill, Grant N ^a,b   Kass, Steven R ^a  

^a University of Minnesota   (United States)

^b IOWA STATE UNIVERSITY   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

ANION; AROMATIC COMPOUND;

ARTICLE; CALCULATION; CHEMICAL ANALYSIS; CHEMICAL STRUCTURE; ENERGY TRANSFER; ISOMERISM; MOLECULAR INTERACTION; THEORY;

EID: 0031576661     PISSN: 00027863     EISSN: None     Source Type: Journal    
DOI: 10.1021/ja9710565     Document Type: Article

References (132)

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56. -1 (MP2).
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63. Lee, C.; Yang, W.; Paar, R. G. Phys. Rev. B 1988, 37, 785. As has been noted by Becke (Becke, A. D. J. Chem. Phys. 1996, 104, 1040), the LYP functional suffers from an inability to reproduce the homogeneous electron gas limit exactly and treat opposite-and parallel-spin correlations uniquely.
64. Lee, C.; Yang, W.; Paar, R. G. Phys. Rev. B 1988, 37, 785. As has been noted by Becke (Becke, A. D. J. Chem. Phys. 1996, 104, 1040), the LYP functional suffers from an inability to reproduce the homogeneous electron gas limit exactly and treat opposite-and parallel-spin correlations uniquely.
65. It should be noted that the original "hybrid" functional of Becke made use of the nonlocal correlation functional of Perdew and Wang (see: Perdew, J. P. Phys. Rev. Lett. 1985, 55, 1665.). Becke, A. D. J. Chem. Phys. 1993, 98, 5648. The Becke3-LYP and Becke3-P86 functional forms are Gaussian 92/DFT and Gaussian 94 implementations.
66. It should be noted that the original "hybrid" functional of Becke made use of the nonlocal correlation functional of Perdew and Wang (see: Perdew, J. P. Phys. Rev. Lett. 1985, 55, 1665.). Becke, A. D. J. Chem. Phys. 1993, 98, 5648. The Becke3-LYP and Becke3-P86 functional forms are Gaussian 92/DFT and Gaussian 94 implementations.
67. Pople, J. A.; Scott, A. P.; Wong, M. W.; Radom, L. Isr. J. Chem. 1993, 33, 345.
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77. Gaussian 94, Revisions A, B, and C; Frisch, M. J.; Trucks, G. W.; Schlegel, H. B.; Gill, P. M. W.; Johnson, B. G.; Robb, M. A.; Cheeseman, J. R.; Keith, T.; Petersson, G. A.; Montgomery, J. A.; Raghavachari, K.; Al-Laham, M. A.; Zakrzewski, V. G.; Ortiz, J. V.; Foresman, J. B.; Cioslowski, J.; Stefanov, B. B.; Nanayakkara, A.; Challacombe, M.; Peng, C. Y.; Ayala, P. Y.; Chen, W.; Wong, M. W.; Andres, J. L.; Replogle, E. S.; Gomperts, R.; Martin, R. L.; Fox, D. J.; Binkley, J. S.; Defrees, D. J.; Baker, J.; Stewart, J. P.; Head-Gordon, M.; Gonzalez, C.; Pople, J. A.; Gaussian, Inc.: Pittsburgh, PA, 1995.
78. The symmetry and gross structure of cyclopropenyl radical has been determined from its ESR spectrum. See: Closs, G. L.; Redwine, O. D. J. Am. Chem. Soc. 1986, 108, 506. The allylic C-H bond dissociation energy for cyclopropene also has been reported (DeFrees, D. J.; McIver, R. T.; Hehre, W. J. J. Am. Chem. Soc. 1980, 102, 3335), but the value has been questioned (Chen, P. In Advances in Carbene Chemistry; Brinker, U., Ed.; JAI Press: Greenwich, CT, 1997, Vol. 2. We thank Professor Chen for making this article available to us before its publication).
79. The symmetry and gross structure of cyclopropenyl radical has been determined from its ESR spectrum. See: Closs, G. L.; Redwine, O. D. J. Am. Chem. Soc. 1986, 108, 506. The allylic C-H bond dissociation energy for cyclopropene also has been reported (DeFrees, D. J.; McIver, R. T.; Hehre, W. J. J. Am. Chem. Soc. 1980, 102, 3335), but the value has been questioned (Chen, P. In Advances in Carbene Chemistry; Brinker, U., Ed.; JAI Press: Greenwich, CT, 1997, Vol. 2. We thank Professor Chen for making this article available to us before its publication).
80. The symmetry and gross structure of cyclopropenyl radical has been determined from its ESR spectrum. See: Closs, G. L.; Redwine, O. D. J. Am. Chem. Soc. 1986, 108, 506. The allylic C-H bond dissociation energy for cyclopropene also has been reported (DeFrees, D. J.; McIver, R. T.; Hehre, W. J. J. Am. Chem. Soc. 1980, 102, 3335), but the value has been questioned (Chen, P. In Advances in Carbene Chemistry; Brinker, U., Ed.; JAI Press: Greenwich, CT, 1997, Vol. 2. We thank Professor Chen for making this article available to us before its publication).
81. Cyclopropene is well-described by a single configuration and thus the MCSCF geometry would not be expected to reproduce the experimental structure any better than the HF data. For experimental data, see: (a) Benson, R. C.; Flygare, W. H. J. Chem. Phys. 1969, 51, 3087. (b) Stigliani, W. M.; Laurie, V. W.; Li, J. C. J. Chem. Phys. 1975, 63, 1890.
82. Cyclopropene is well-described by a single configuration and thus the MCSCF geometry would not be expected to reproduce the experimental structure any better than the HF data. For experimental data, see: (a) Benson, R. C.; Flygare, W. H. J. Chem. Phys. 1969, 51, 3087. (b) Stigliani, W. M.; Laurie, V. W.; Li, J. C. J. Chem. Phys. 1975, 63, 1890.
83. In this work all of the reported atomic charges have the hydrogen contributions summed into the carbon atoms.
84. The cyclopropenyl anion wave functions contain anywhere from 2676 (5) to 7560 (11) configurations. The CSF coefficient is 0.956 and thus 9% of the MCSCF wave function is made up of open-shell configurations.
85. Löwdin, P. O. Phys. Rev. 1955, 97, 1474.
86. When NOONs deviate by more than 0.07-0.1 from the closed-shell configuration, a multiconfiguration wave function is generally warranted. (a) Bone, R. G. A.; Pulay, P. Int. J. Quantum Chem. 1993, 45, 133. (b) Bofill, J. M.; Pulay, P. J. Chem. Phys. 1989, 90, 3637. (c) Pulay, P.; Hamilton, T. P. J. Chem. Phys. 1988, 88, 4926.
87. When NOONs deviate by more than 0.07-0.1 from the closed-shell configuration, a multiconfiguration wave function is generally warranted. (a) Bone, R. G. A.; Pulay, P. Int. J. Quantum Chem. 1993, 45, 133. (b) Bofill, J. M.; Pulay, P. J. Chem. Phys. 1989, 90, 3637. (c) Pulay, P.; Hamilton, T. P. J. Chem. Phys. 1988, 88, 4926.
88. When NOONs deviate by more than 0.07-0.1 from the closed-shell configuration, a multiconfiguration wave function is generally warranted. (a) Bone, R. G. A.; Pulay, P. Int. J. Quantum Chem. 1993, 45, 133. (b) Bofill, J. M.; Pulay, P. J. Chem. Phys. 1989, 90, 3637. (c) Pulay, P.; Hamilton, T. P. J. Chem. Phys. 1988, 88, 4926.
89. The CSF coefficient is 0.941, and thus 11.5% of the wave function is made up of open-shell determinants.
90. The CSF coefficients for the lowest energy open-shell configuration are both 0.973.
91. In this case the CSF coefficient is 0.974.
92. For recent calculations on the cyclopropenyl radical, see: (a) Byun, Y.-G.; Saebo, S.; Pittman, C. U., Jr. J. Am. Chem. Soc. 1991, 113, 3689. (b) Jensen, F. Chem. Phys. Lett. 1989, 161, 368. (c) Usha, G.; Rao, B. N.; Chandrasekhar, J.; Ramamurthy, V. J. Org. Chem. 1986, 51, 3630. (d) Hoffmann, M. R.; Laidig, W. D.; Kim, K. S.; Fox, D. J.; Schaefer, H. F. J. Chem. Phys. 1984, 80, 338.
93. For recent calculations on the cyclopropenyl radical, see: (a) Byun, Y.-G.; Saebo, S.; Pittman, C. U., Jr. J. Am. Chem. Soc. 1991, 113, 3689. (b) Jensen, F. Chem. Phys. Lett. 1989, 161, 368. (c) Usha, G.; Rao, B. N.; Chandrasekhar, J.; Ramamurthy, V. J. Org. Chem. 1986, 51, 3630. (d) Hoffmann, M. R.; Laidig, W. D.; Kim, K. S.; Fox, D. J.; Schaefer, H. F. J. Chem. Phys. 1984, 80, 338.
94. For recent calculations on the cyclopropenyl radical, see: (a) Byun, Y.-G.; Saebo, S.; Pittman, C. U., Jr. J. Am. Chem. Soc. 1991, 113, 3689. (b) Jensen, F. Chem. Phys. Lett. 1989, 161, 368. (c) Usha, G.; Rao, B. N.; Chandrasekhar, J.; Ramamurthy, V. J. Org. Chem. 1986, 51, 3630. (d) Hoffmann, M. R.; Laidig, W. D.; Kim, K. S.; Fox, D. J.; Schaefer, H. F. J. Chem. Phys. 1984, 80, 338.
95. For recent calculations on the cyclopropenyl radical, see: (a) Byun, Y.-G.; Saebo, S.; Pittman, C. U., Jr. J. Am. Chem. Soc. 1991, 113, 3689. (b) Jensen, F. Chem. Phys. Lett. 1989, 161, 368. (c) Usha, G.; Rao, B. N.; Chandrasekhar, J.; Ramamurthy, V. J. Org. Chem. 1986, 51, 3630. (d) Hoffmann, M. R.; Laidig, W. D.; Kim, K. S.; Fox, D. J.; Schaefer, H. F. J. Chem. Phys. 1984, 80, 338.
96. The CSF coefficients are 0.962 and 0.127, respectively.
97. Coefficients associated with the lowest energy doublet and the sums of the quadruple and doubly excited CSFs are 0.945, 0.195, and 0.253, respectively.
98. - for the singlets.
99. If a larger basis set than 6-31+G(d) or 6-31+G(d,p) is used (i.e., 6-311+G(2df,2pd)) or an MP3 optimization is carried out, the structure changes relatively little (especially in the former case), but the anion does become a TS.
100. (a) Merrill, G. N.; Gronert, S.; Kass, S. R. J. Phys. Chem. A 1997, 101, 208.
101. (b) Baker, J.; Andzelm, J.; Muir, M.; Taylor, P. R. Chem. Phys. Lett. 1995, 237, 53.
102. (c) Latajka, Z.; Bouteiller, Y.; Scheiner, S. Chem. Phys. Lett. 1995, 234, 159.
103. (d) Pederson, M. R. Chem. Phys. Lett. 1994, 230, 54.
104. (e) Johnson, B. G.; Gonzales, C. A.; Gill, P. M. W.; Pople, J. A. Chem. Phys. Lett. 1994, 221, 100.
105. (f) Stanton, R. V.; Merz, K. M., Jr. J. Chem. Phys. 1994, 100, 434.
106. (g) Fan, L.; Ziegler, T. J. Am. Chem. Soc. 1992, 114, 10890.
107. The experimental proton affinity was corrected to 0 K by using MP2/6-31+G(d,p) vibrational frequencies. For a critical review of measured thermodynamic data, see: Berkowitz, J.; Ellison, G. B.; Gutman, D. J. Phys. Chem. 1994, 98, 2744.
108. The proton affinity of the cyclopropyl anion is calculated to be 411.3 and 413.2 kcal/mol at the CCSD(T)//MP2/6-31+G(d,p) and CCSD(T)//MCSCF[6,6]/6-31+G(d,p) levels, respectively. These results are in good agreement with an experimental determination of 411.5 (see ref 11). For the purposes of comparison (and consistency), we have employed the calculated value using the MCSCF geometry.
109. Merrill, G. N.; Kass, S. R. J. Phys. Chem. 1996, 100, 17465.
110. 2〉 value of 0.763.
111. 2〉 values for the radical wave functions are 0.753, 0.752, 0.753, and 0.762 for B-VWN5, B-LYP, B3-LYP, and MP2, respectively.
112. Pople, J. A.; Schleyer, P. v. R.; Kaneti, J.; Spitznagel, G. W. Chem. Phys. Lett. 1988, 145, 359.
113. (a) Falcetta, M. F.; Jordan, K. D. J. Am. Chem. Soc. 1991, 113, 2903.
114. (b) Chao, J. S.-Y.; Falcetta, M. F.; Jordan, K. D. J. Chem. Phys. 1990, 93, 1125.
115. It is also worth noting that if one carries out a "free" electron calculation (see ref 46) to obtain the one-electron continuum, the singly occupied MO energy level lies above that of the anion. This also suggests that our calculations do not correspond to radical + free electron solutions.
116. · is -0.51969 hartree, which is in error by 12.3 kcal/mol from the exact value of -0.5 hartree.
117. Montgomery, J. A., Jr.; Ochterski, J. W.; Petersson, G. A. J. Chem. Phys. 1994, 101, 5900.
118. At 0 K this value will drop to ∼102 kcal/mol.
119. The isomeric 1-cyanocyclopropene is 1.4 kcal/mol higher in energy than 12 at the MP2/6-31+G(d)//HF/6-31+G(d) level. The corresponding cyclopropenyl anion also was found to be an energy minimum at the HF level. It is 9.5 kcal/mol higher in energy than 13 (MP2/6-31+G(d)//HF/6-31+G(d)) and disappears from the potential surface at the MP2 level. For further details, see: Sachs, R. K. Ph.D. Thesis, University of Minnesota, 1993.
120. For comparison purposes, the average of the MP2/HF, MP2, B-VWN5, B-LYP, and B3-LYP differences (i.e., 9.4, 9.9, 9.4, 9.3, and 10.0 kcal/mol, respectively) was used. In addition, PA(cyclopropyl anion-cyanocyclopropyl anion) - PA(cyclopropenyl anion-cyanocyclopropenyl anion) = 37.7 - 34.0 or 3.7 kcal/mol.
121. 2v cyanocyclopropenyl anion has one imaginary frequency at the HF/6-31+G(d,p) level (411i), but this increases to three at the MP2/6-31+G(d,p) level (167i, 195i, 635i).
122. Cramer, C. J.; Dulles, F. J.; Storer, J. W.; Worthington, S. E. Chem. Phys. Lett. 1994, 218, 387.
123. 298(13) = 122 kcal/mol.
124. Benson, S. W. Thermochemical Kinetics, 2nd ed.; John Wiley and Sons: New York, 1976.
125. 2) = 118 kcal/mol (ref 25).
126. This quantity was corrected to 298 K by using MP2/6-31+G(d) vibrational frequencies and a scaling factor of 0.9427.
127. 1,2-Dicyanocyclopropene (19) is slightly more stable than 20 at most levels of theory that were explored (i.e., ΔE(20-19) = -2.64 (HF), -0.11 (MP2//HF), 0.41 (MP2), 2.95 (B-VWN5), 2.74 (B-LYP), and 1.34 (B3-LYP) kcal/mol.
128. Other symmetries were explored but were found to be second-order or higher saddle points.
129. 1 structure could be located.
130. 2Me and CN should be small and can be ignored for these purposes.
131. Breslow, R.; Cortes, D. A.; Jaun, B.; Mitchell, R. D. Tetrahedron Lett. 1982, 23, 795.
132. Ring-opening processes and radical chemistry via the triplet also must be circumvented if a stable cyclopropenyl anion is to be prepared.