-
6
-
-
33947337525
-
-
(b) Wasserman, E.; Murray, R. W.; Yager, W. A.; Trozzolo, A. M.; Smolinsky, G. J. Am. Chem. Soc. 1967, 89, 5076.
-
(1967)
J. Am. Chem. Soc.
, vol.89
, pp. 5076
-
-
Wasserman, E.1
Murray, R.W.2
Yager, W.A.3
Trozzolo, A.M.4
Smolinsky, G.5
-
8
-
-
0032508939
-
-
(a) Subhan, W.; Rempala, P.; Sheridan, R. S. J. Am. Chem. Soc. 1998, 120, 11528.
-
(1998)
J. Am. Chem. Soc.
, vol.120
, pp. 11528
-
-
Subhan, W.1
Rempala, P.2
Sheridan, R.S.3
-
11
-
-
0041521876
-
-
(a) Tomioka, H.; Komatsu, K.; Nakayama, T.; Shimizu, M. Chem. Lett. 1993, 1291.
-
(1993)
Chem. Lett.
, pp. 1291
-
-
Tomioka, H.1
Komatsu, K.2
Nakayama, T.3
Shimizu, M.4
-
12
-
-
0032508947
-
-
(b) Nicolaides, A.; Tomioka, H.; Murata, S. J. Am. Chem. Soc. 1998, 120, 11530.
-
(1998)
J. Am. Chem. Soc.
, vol.120
, pp. 11530
-
-
Nicolaides, A.1
Tomioka, H.2
Murata, S.3
-
13
-
-
0034820005
-
-
Nicolaides, A.; Enyo, T.; Miura, D.; Tomioka, H. J. Am. Chem. Soc. 2001, 123, 2628.
-
(2001)
J. Am. Chem. Soc.
, vol.123
, pp. 2628
-
-
Nicolaides, A.1
Enyo, T.2
Miura, D.3
Tomioka, H.4
-
14
-
-
0033579138
-
-
Nicolaides, A.; Nakayma, T.; Yamazaki, K.; Tomioka, H.; Koseki, S.; Stracener, L. L.; McMahon, R. J. J. Am. Chem. Soc. 1999, 121, 10563.
-
(1999)
J. Am. Chem. Soc.
, vol.121
, pp. 10563
-
-
Nicolaides, A.1
Nakayma, T.2
Yamazaki, K.3
Tomioka, H.4
Koseki, S.5
Stracener, L.L.6
McMahon, R.J.7
-
15
-
-
0029989970
-
-
(a) Matzinger, S.; Bally, T.; Patterson, E. V.; McMahon, R. J. J. Am. Chem. Soc. 1996, 118, 1535.
-
(1996)
J. Am. Chem. Soc.
, vol.118
, pp. 1535
-
-
Matzinger, S.1
Bally, T.2
Patterson, E.V.3
McMahon, R.J.4
-
17
-
-
0000827672
-
-
(c) Schreiner, P. R.; Karney, W. L.; Schleyer, P. V.; Borden, W. T.; Hamilton, T. P., Schaefer, H. F. J. Org. Chem. 1996, 61, 7030.
-
(1996)
J. Org. Chem.
, vol.61
, pp. 7030
-
-
Schreiner, P.R.1
Karney, W.L.2
Schleyer, P.V.3
Borden, W.T.4
Hamilton, T.P.5
Schaefer, H.F.6
-
18
-
-
0000757043
-
-
(d) Cramer, C. J.; Dulles, F. J.; Falvey, D. E. J. Am. Chem. Soc. 1994, 116, 9787.
-
(1994)
J. Am. Chem. Soc.
, vol.116
, pp. 9787
-
-
Cramer, C.J.1
Dulles, F.J.2
Falvey, D.E.3
-
19
-
-
0001706391
-
-
Hrovat, D. A.; Waali, E. E.; Borden, W. T. J. Am. Chem. Soc. 1992, 114, 8698.
-
(1992)
J. Am. Chem. Soc.
, vol.114
, pp. 8698
-
-
Hrovat, D.A.1
Waali, E.E.2
Borden, W.T.3
-
20
-
-
0003639797
-
-
Hund, F. Z. Phys. 1928, 51, 759.
-
(1928)
Z. Phys.
, vol.51
, pp. 759
-
-
Hund, F.1
-
22
-
-
0001142932
-
-
(b) Borden, W. T.; Iwamura, H.; Berson, J. Acc. Chem. Res. 1994, 27, 109.
-
(1994)
Acc. Chem. Res.
, vol.27
, pp. 109
-
-
Borden, W.T.1
Iwamura, H.2
Berson, J.3
-
23
-
-
24944557984
-
-
note
-
The weakness of this π-bond is presumably due to the loss of the aromaticity of the benzene ring in the ground states.
-
-
-
-
24
-
-
0001767095
-
-
As measured by photoelectron spectroscopy. (a) Travers, M. J.; Cowles, D. D.; Clifford, E. P.; Ellison, G. B. J. Am. Chem. Soc. 1992, 114, 1699.
-
(1992)
J. Am. Chem. Soc.
, vol.114
, pp. 1699
-
-
Travers, M.J.1
Cowles, D.D.2
Clifford, E.P.3
Ellison, G.B.4
-
26
-
-
0000943065
-
-
Mueller, P. M.; Rondan, N. G.; Houk, K. N.; Harrison, J. F.; Hooper, D.; Willen, B. H.; Liebman, J. F. J. Am. Chem. Soc. 1981, 103, 5049.
-
(1981)
J. Am. Chem. Soc.
, vol.103
, pp. 5049
-
-
Mueller, P.M.1
Rondan, N.G.2
Houk, K.N.3
Harrison, J.F.4
Hooper, D.5
Willen, B.H.6
Liebman, J.F.7
-
27
-
-
24944536691
-
-
note
-
The best linear fit has a slope of 0.97 (1.00), an intercept of -4.4 kcal/mol (-3.0 kcal/mol), and a squared-regression coefficient of 0.9965 at the CASPT2 (MCSCF) level of theory.
-
-
-
-
28
-
-
24944492895
-
-
note
-
At the MCSCF level, the values are -0.90, 29.6 kcal/mol, and 0.9968, respectively.
-
-
-
-
29
-
-
0003053470
-
-
This can be realized with a substituent that is a stronger π-donor than F, as for example with an amino or even perhaps with a hydroxy one. Feller, D.; Borden, W. T.; Davidson, E. R. Chem. Phys. Lett. 1980, 71, 22.
-
(1980)
Chem. Phys. Lett.
, vol.71
, pp. 22
-
-
Feller, D.1
Borden, W.T.2
Davidson, E.R.3
-
30
-
-
24944455871
-
-
note
-
-1 peak. Indeed, the ratio of the areas of the two peaks is about 1.4, which compares favorably to the 3:1 ratio of corresponding computed intensities.
-
-
-
-
31
-
-
24944476531
-
-
note
-
-1 are also predicted, these are very weak (7, 7, and 2 km/mol, respectively) and not likely to be observable under our experimental conditions.
-
-
-
-
32
-
-
24944490022
-
-
note
-
Apart from Z- and E-6-BrN the following aminocarbene and two cycloalkynes were screened computationally, but it is unlikely that they were formed.
-
-
-
-
33
-
-
24944554484
-
-
note
-
The UV/vis spectra also provide some evidence for this, since the band due to the initial photoproduct was notably weaker in the photolysis of 1-FN as opposed to that in photolysis of 1-ClN and 1-BrN.
-
-
-
-
34
-
-
0000436067
-
-
Rao, K. N., Ed.; Academic Press: New York
-
(a) Pugh, L. A.; Narahari Rao, K. In Molecular Spectroscopy: Modern Research; Rao, K. N., Ed.; Academic Press: New York, 1976; Vol. II, pp 165-227.
-
(1976)
Molecular Spectroscopy: Modern Research
, vol.2
, pp. 165-227
-
-
Pugh, L.A.1
Narahari Rao, K.2
-
35
-
-
0035819977
-
-
(b) For an interesting case of comparing computed and experimental IR spectra, see: Friderichsen, A. V.; Radziszewski, J. G.; Nimlos, M. R.; Winter, P. R.; Dayton, D. C.; David, D. E.; Ellison, G. B. J. Am. Chem. Soc. 2001, 123, 1977.
-
(2001)
J. Am. Chem. Soc.
, vol.123
, pp. 1977
-
-
Friderichsen, A.V.1
Radziszewski, J.G.2
Nimlos, M.R.3
Winter, P.R.4
Dayton, D.C.5
David, D.E.6
Ellison, G.B.7
-
36
-
-
24944489205
-
-
note
-
-1 (32 km/mol) for 4-FN, 4-ClN, and 4-BrN, respectively.
-
-
-
-
37
-
-
24944502239
-
-
note
-
The reported calculations refer to thermal reactions, which are unlikely to be taking place under our experimental conditions. It is more likely that the diradicals 2-XN are extremely photochemically reactive and once formed are rapidly converted to the observed products. Alternatively, excited states of the precursors 1-XN or intermediates resulting from the loss of one nitrogen molecule (e.g., nitrenediazirines) could give rise to the observed products by simultaneous loss of nitrogen. While these more likely processes may give product ratios that reflect the ground-state proclivities of the diradicals, this can neither be proved nor disproved by the current data.
-
-
-
-
38
-
-
24944523242
-
-
note
-
1A′-2-ClN, E-6-ClN, Z-6-ClN these are: -0.26 (0.14), -0.32 (0.06), and 0.00 (0.43), respectively.
-
-
-
-
40
-
-
0000318498
-
-
19F NMR. Janulis, E. P., Jr.; Arduengo, A. J., III. J. Am. Chem. Soc. 1983, 105, 3563.
-
(1983)
J. Am. Chem. Soc.
, vol.105
, pp. 3563
-
-
Janulis Jr., E.P.1
Arduengo III, A.J.2
-
41
-
-
24944543894
-
-
note
-
The biradical is described by a spin-broken symmetry wave function while Z-6-XN is a closed-shell singlet. Attempts to locate the transition state were unsuccessful, as the calculation seemed to wander from the open-shell surface to the closed one. Apparently an MCSCF treatment is required, and it is quite possible that a conical intersection connects the two singlet surfaces. However, this also may not be enough since the vibrational mode connecting the two isomers may need to be taken into account at the same time. Whatever the case, this is beyond the scope of the current work.
-
-
-
-
44
-
-
24944448650
-
-
note
-
31 This correlation is similar to that for 2-XN.
-
-
-
-
45
-
-
24944537036
-
-
note
-
The energy of the transition structure connecting E,E-2-ClC with 3-ClC is 0.1 kcal/mol higher than that of E,E-2-ClC, but it becomes lower (by 0.2 kcal/mol, Figure 5a) when ZPE corrections are included. Thus, this barrier is small (if it exists at all) and is in agreement with the MCSCF result of "spontaneous" ring closing to 3-ClC.
-
-
-
-
46
-
-
24944464979
-
-
note
-
Ignoring the small energy differences between the four isomers and assuming that all are formed in equal amounts, the data in Figure 5 suggest that more than 25% of the (3-ClC and 4-ClC) mixture should be 4-ClC.
-
-
-
-
47
-
-
24944433069
-
-
note
-
For reasons analogous to the ones mentioned in ref 30, attempts to locate a transition structure for the Z,E-2-ClC to Z-6-ClC isomerization were unsuccessful.
-
-
-
-
48
-
-
0034801403
-
-
Nicolaides, A.; Matsushita, T.; Yonezawa, K.; Shinji, S.; Tomioka, H.; Stracener, L. L.; Hodges, J. A.; McMahon, R. J. J. Am. Chem. Soc. 2001, 123, 2870.
-
(2001)
J. Am. Chem. Soc.
, vol.123
, pp. 2870
-
-
Nicolaides, A.1
Matsushita, T.2
Yonezawa, K.3
Shinji, S.4
Tomioka, H.5
Stracener, L.L.6
Hodges, J.A.7
McMahon, R.J.8
-
49
-
-
4243661307
-
-
-1 area can be attributed to weak hot bands of acetylenic compounds (Klaboe, P.; Klosterjensen, E.; Bjarnov, E.; Christensen, D. H.; Nielsen, O. F. Spectrochim. Acta 1975, 31A, 931), thus making doubtful the observation of 4-ClC. However, this would only increase the observed [3-ClC]/[4-ClC] ratio, strengthening the argument presented in the next section.
-
(1975)
Spectrochim. Acta
, vol.31 A
, pp. 931
-
-
Klaboe, P.1
Klosterjensen, E.2
Bjarnov, E.3
Christensen, D.H.4
Nielsen, O.F.5
-
50
-
-
0004133516
-
-
Gaussian Inc.: Pittsburgh, PA
-
(a) Frisch, M. J. et al. Gaussian 94; Gaussian Inc.: Pittsburgh, PA, 1995.
-
(1995)
Gaussian 94
-
-
Frisch, M.J.1
-
53
-
-
0003392598
-
-
Lund University: Lund, Sweden
-
Roos, B. O. et al. MOLCAS, version 5.2; Lund University: Lund, Sweden 2000.
-
(2000)
MOLCAS, Version 5.2
-
-
Roos, B.O.1
-
54
-
-
0345491105
-
-
(a) Lee, C.; Yang, W.; Parr, R. G. Phys. Rev. B 1988, 37, 785.
-
(1988)
Phys. Rev. B
, vol.37
, pp. 785
-
-
Lee, C.1
Yang, W.2
Parr, R.G.3
-
55
-
-
0038596731
-
-
(b) Miehlich, B.; Savin, A.; Stoll, H.; Preuss, H. Chem. Phys. Lett. 1989, 157, 200.
-
(1989)
Chem. Phys. Lett.
, vol.157
, pp. 200
-
-
Miehlich, B.1
Savin, A.2
Stoll, H.3
Preuss, H.4
-
58
-
-
0033449808
-
-
Lipowitz, K. B.; Boyd, D. B., Eds., Wiley: New York
-
For a review on calculations for open-shell species, see: Bally, T.; Borden, W. T. In Reviews in Computational Chemistry; Lipowitz, K. B.; Boyd, D. B., Eds., Wiley: New York, 1999; Vol. 13, p 1.
-
(1999)
Reviews in Computational Chemistry
, vol.13
, pp. 1
-
-
Bally, T.1
Borden, W.T.2
|