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Journal of the American Chemical Society

Volumn 101, Issue 22, 1979, Pages 6687-6693

Interdependence of Solvolysis Rate and Aryl-Aryl Dihedral Angle in a Series of 4-Biphenylyldimethylcarbinyl p-Nitrobenzoates

(3) Katsuo, Ohkata a Paquette, Ronald L a Paquette, Leo A a

a OHIO STATE UNIVERSITY (United States)

Author keywords

[No Author keywords available]

Indexed keywords

EID: 0013561173 PISSN: 00027863 EISSN: 15205126 Source Type: Journal
DOI: 10.1021/ja00516a034 Document Type: Article

Times cited : (27)

References (86)

1
- 0000265548
- Paquette, L.A., Angew. Chem., 1978, 90, 114.
- (1978) Angew. Chem. , vol.90 , pp. 114
- Paquette, L.A.¹

2
- 0000871281
- Paquette, L.A., Angew. Chem., Int. Ed. Engl., 1978, 17, 106.
- (1978) Angew. Chem. , vol.17 , pp. 106
- Paquette, L.A.¹

3
- 85023232111
- Hirokawa: Tokyo
- Warner, P., “Topics in Nonbenzenoic Aromatic Chemistry”, Vol. II; Hirokawa: Tokyo, 1977.
- (1977) Topics in Nonbenzenoic Aromatic Chemistry , vol.1
- Warner, P.¹

4
- 0002180299
- Winstein, S., Chem. Soc., Spec. Publ., 1967, No. 21, 5.
- (1967) Chem. Soc. , vol.21 , pp. 5
- Winstein, S.¹

5
- 0000279669
- Winstein, S., Q. Rev. Chem. Soc., 1969, 23, 141.
- (1969) Q. Rev. Chem. Soc. , vol.23 , pp. 141
- Winstein, S.¹

6
- 0013380104
- Paquette, L.A.; Wallis, T.G.; Kempe, T.; Christoph, G.G.; Springer, J.P.; Clardy, J., J. Am. Chem. Soc., 1977, 99, 6946.
- (1977) J. Am. Chem. Soc. , vol.99 , pp. 6946
- Paquette, L.A.¹ Wallis, T.G.² Kempe, T.³ Christoph, G.G.⁴ Springer, J.P.⁵ Clardy, J.⁶

7
- 33947093044
- Christoph, G.G.; Muthard, J.L.; Paquette, L.A.; Bohm, M.C.; Gleiter, R., J. Am. Chem. Soc., 1978, 100, 7782.
- (1978) J. Am. Chem. Soc. , vol.100 , pp. 7782
- Christoph, G.G.¹ Muthard, J.L.² Paquette, L.A.³ Bohm, M.C.⁴ Gleiter, R.⁵

8
- 33947093923
- Paquette, L.A.; Ewing, G.D.; Ley, S.V.; Berk, H.C.; Traynor, S.G., J. Org. Chem., 1978, 43, 4712.
- (1978) J. Org. Chem. , vol.43 , pp. 4712
- Paquette, L.A.¹ Ewing, G.D.² Ley, S.V.³ Berk, H.C.⁴ Traynor, S.G.⁵

9
- 33947094022
- Berk, H.C.; Degenhardt, C.R.; Paquette, L.A., J. Org. Chem., 1978, 43, 4516.
- (1978) J. Org. Chem. , vol.43 , pp. 4516
- Berk, H.C.¹ Degenhardt, C.R.² Paquette, L.A.³

10
- 33947093527
- Paquette, L.A.; Detty, M.R., J. Am. Chem. Soc., 1978, 100, 5856.
- (1978) J. Am. Chem. Soc. , vol.100 , pp. 5856
- Paquette, L.A.¹ Detty, M.R.²

11
- 33947094887
- Paquette, L.A.; Degenhardt, C.R.; Berk, H.C., J. Am. Chem. Soc., 1978, 100, 1599.
- (1978) J. Am. Chem. Soc. , vol.100 , pp. 1599
- Paquette, L.A.¹ Degenhardt, C.R.² Berk, H.C.³

12
- 0038614488
- Spanget-Larsen, J.; Gleiter, R.; Detty, M.R.; Paquette, L.A., J. Am. Chem. Soc., 1978, 100, 3005.
- (1978) J. Am. Chem. Soc. , vol.100 , pp. 3005
- Spanget-Larsen, J.¹ Gleiter, R.² Detty, M.R.³ Paquette, L.A.⁴

13
- 33947092182
- Domelsmith, L.N.; Houk, K.N.; Degenhardt, C.R.; Paquette, L.A., J. Am. Chem. Soc., 1978, 100, 100.
- (1978) J. Am. Chem. Soc. , vol.100 , pp. 100
- Domelsmith, L.N.¹ Houk, K.N.² Degenhardt, C.R.³ Paquette, L.A.⁴

14
- 0000925488
- Paquette, L.A.; Liao, C.C.; Burson, R.L., Wingard, R. E., Jr.; Shih, C.N.; Fayos, J.; Clardy, J., J. Am. Chem. Soc., 1977, 99, 6935.
- (1977) J. Am. Chem. Soc. , vol.99 , pp. 6935
- Paquette, L.A.¹ Liao, C.C.² Burson, R.L.³ Wingard, R, E.⁴ Shih, C.N.⁵ Fayos, J.⁶ Clardy, J.⁷

15
- 33847090189
- Paquette, L.A.; Lavrik, P.B.; Summerville, R.H., J. Org. Chem., 1977, 42, 2659.
- (1977) J. Org. Chem. , vol.42 , pp. 2659
- Paquette, L.A.¹ Lavrik, P.B.² Summerville, R.H.³

16
- 1942498039
- Paquette, L.A.; Berk, H.C.; Degenhardt, C.R.; Ewing, G.D., J. Am. Chem. Soc., 1977, 99, 4764.
- (1977) J. Am. Chem. Soc. , vol.99 , pp. 4764
- Paquette, L.A.¹ Berk, H.C.² Degenhardt, C.R.³ Ewing, G.D.⁴

17
- 0012220272
- Paquette, L.A.; Kukla, M.J.; Ley, S.v.; Traynor, S.G., J. Am. Chem. Soc., 1977, 99, 4756.
- (1977) J. Am. Chem. Soc. , vol.99 , pp. 4756
- Paquette, L.A.¹ Kukla, M.J.² Ley, S.v.³ Traynor, S.G.⁴

18
- 0011231939
- Detty, M.R.; Paquette, L.A., Tetrahedron Lett., 1977, 347.
- (1977) Tetrahedron Lett. , pp. 347
- Detty, M.R.¹ Paquette, L.A.²

19
- 33847088610
- Detty, M.R.; Paquette, L.A., J. Am. Chem. Soc., 1977, 99, 821, 828, 834.
- (1977) J. Am. Chem. Soc.
- Detty, M.R.¹ Paquette, L.A.²

20
- 0346062333
- Paquette, L.A.; Ley, S.V.; Traynor, S.G.; Martin, J.T.; Geckle, J.M., J. Am. Chem. Soc., 1976, 98, 8162.
- (1976) J. Am. Chem. Soc. , vol.98 , pp. 8162
- Paquette, L.A.¹ Ley, S.V.² Traynor, S.G.³ Martin, J.T.⁴ Geckle, J.M.⁵

21
- 33646273700
- Paquette, L.A.; Jacobsson, U.; Ley, S.V., J. Am. Chem. Soc., 1976, 98, 152.
- (1976) J. Am. Chem. Soc. , vol.98 , pp. 152
- Paquette, L.A.¹ Jacobsson, U.² Ley, S.V.³

22
- 0000128736
- Bischof, P.; Bosse, D.; Gleiter, R.; Kukla, M.J.; de Meijere, A.; Paquette, L.A., Chem. Ber., 1975, 108, 1218.
- (1975) Chem. Ber. , vol.108 , pp. 1218
- Bischof, P.¹ Bosse, D.² Gleiter, R.³ Kukla, M.J.⁴ de Meijere, A.⁵ Paquette, L.A.⁶

23
- 33947480836
- Brown, H.C.; Dubeck, M.; Goldman, G., J. Am. Chem. Soc., 1962, 84, 1229.
- (1962) J. Am. Chem. Soc. , vol.84 , pp. 1229
- Brown, H.C.¹ Dubeck, M.² Goldman, G.³

24
- 0343993182
- Brown, H.C.; Neyens, A.H., J. Am. Chem. Soc., 1962, 84, 1233.
- (1962) J. Am. Chem. Soc. , vol.84 , pp. 1233
- Brown, H.C.¹ Neyens, A.H.²

25
- 0011644312
- Brown, H.C.; Marino, G., J. Am. Chem. Soc., 1962, 84, 1236.
- (1962) J. Am. Chem. Soc. , vol.84 , pp. 1236
- Brown, H.C.¹ Marino, G.²

26
- 0004678337
- Brown, H.C.; Stock, L.M., J. Am. Chem. Soc., 1962, 84, 1238.
- (1962) J. Am. Chem. Soc. , vol.84 , pp. 1238
- Brown, H.C.¹ Stock, L.M.²

27
- 57149112858
- Ed.; Butterworths: London
- Brown, H.C. “Steric Effects in Conjugated Systems”, Grey, G.W., Ed.; Butterworths: London, 1958, pp 100-118.
- (1958) Steric Effects in Conjugated Systems , pp. 100-118
- Brown, H.C.¹ Grey, G.W.²

28
- 5944250383
- de la Mare, P.D.B.; Johnson, E.A.; Lomas, J.S., J. Chem. Soc., 1964, 5317.
- (1964) J. Chem. Soc. , pp. 5317
- de la Mare, P.D.B.¹ Johnson, E.A.² Lomas, J.S.³

29
- 37049044643
- de la Mare, P.B.D.; Lomas, J.S., J. Chem. Soc., 1965, 5739.
- (1965) J. Chem. Soc. , pp. 5739
- de la Mare, P.B.D.¹ Lomas, J.S.²

30
- 84943849038
- Baker, R.; Bott, R.W.; Eaborn, C.; Gresley, P.M., J. Chem. Soc., 1964, 627.
- (1964) J. Chem. Soc. , pp. 627
- Baker, R.¹ Bott, R.W.² Eaborn, C.³ Gresley, P.M.⁴

31
- 26844520799
- Suzuki, H., Bull. Chem. Soc. Jpn., 1954, 27, 597.
- (1954) Bull. Chem. Soc. Jpn. , vol.27 , pp. 597
- Suzuki, H.¹

32
- 84943878671
- Suzuki, H., Bull. Chem. Soc. Jpn., 1959, 32, 1340, 1350, 1357.
- (1959) Bull. Chem. Soc. Jpn.
- Suzuki, H.¹

33
- 33947479707
- Stock, L.M.; Brown, H.C., J. Am. Chem. Soc., 1962, 84, 1242.
- (1962) J. Am. Chem. Soc. , vol.84 , pp. 1242
- Stock, L.M.¹ Brown, H.C.²

34
- 0013600661
- Berliner, E.; Shieh, N., J. Am. Chem. Soc., 1957, 79, 3849.
- (1957) J. Am. Chem. Soc. , vol.79 , pp. 3849
- Berliner, E.¹ Shieh, N.²

35
- 84943056780
- Bolton, R.; Jones, M.E.; Tucker, S.W., J. Chem. Soc., 1964, 1464.
- (1964) J. Chem. Soc. , pp. 1464
- Bolton, R.¹ Jones, M.E.² Tucker, S.W.³

36
- 37049050208
- Bolton, R., J. Chem. Soc., 1965, 1542.
- (1965) J. Chem. Soc. , pp. 1542
- Bolton, R.¹

37
- 0003783017
- Bolton, R.; Burley, R.E.M., J. Chem. Soc., Perkin Trans. 2 1977, 426.
- (1977) J. Chem. Soc. , pp. 426
- Bolton, R.¹ Burley, R.E.M.²

38
- 0001194667
- Brown, H.C.; Brady, J.D.; Grayson, M.; Bonner, W.H., J. Am. Chem. Soc., 1957, 79, 1897.
- (1957) J. Am. Chem. Soc. , vol.79 , pp. 1897
- Brown, H.C.¹ Brady, J.D.² Grayson, M.³ Bonner, W.H.⁴

39
- 7044261128
- Brown, H.C.; Inukai, T., J. Am. Chem. Soc., 1961, 83, 4825.
- (1961) J. Am. Chem. Soc. , vol.83 , pp. 4825
- Brown, H.C.¹ Inukai, T.²

40
- 1542641649
- Tsuno, Y.; Chong, W.-Y.; Tairaka, Y.; Sawada, M.; Yukawa, Y., Bull. Chem. Soc. Jpn., 1978, 51, 596.
- (1978) Bull. Chem. Soc. Jpn. , vol.51 , pp. 596
- Tsuno, Y.¹ Chong, W.-Y.² Tairaka, Y.³ Sawada, M.⁴ Yukawa, Y.⁵

41
- 1542431936
- Tsuno, Y.; Tairaka, Y.; Sawada, M.; Fujii, T.; Yukawa, Y., Bull. Chem. Soc. Jpn., 1978, 51, 601.
- (1978) Bull. Chem. Soc. Jpn. , vol.51 , pp. 601
- Tsuno, Y.¹ Tairaka, Y.² Sawada, M.³ Fujii, T.⁴ Yukawa, Y.⁵

42
- 0000834576
- Yukawa, Y.; Tsuno, Y., Bull. Chem. Soc. Jpn., 1959, 32, 971.
- (1959) Bull. Chem. Soc. Jpn. , vol.32 , pp. 971
- Yukawa, Y.¹ Tsuno, Y.²

43
- 0001651778
- Yukawa, Y.; Tsuno, Y.; Sawada, M., Bull. Chem. Soc. Jpn., 1966, 39, 2274.
- (1966) Bull. Chem. Soc. Jpn. , vol.39 , pp. 2274
- Yukawa, Y.¹ Tsuno, Y.² Sawada, M.³

44
- 0013522874
- Johnson, C.D., J. Org. Chem., 1978, 43, 1814.
- (1978) J. Org. Chem. , vol.43 , pp. 1814
- Johnson, C.D.¹

45
- 85023212533
- Brown, H.C.; Peters, E.N., J. Am. Chem. Soc., 1976, 98, 1712.
- (1976) J. Am. Chem. Soc. , vol.98 , pp. 1712
- Brown, H.C.¹ Peters, E.N.²

46
- 0000171381
- Brown, H.C.; Ravindranathan, M.; Peters, E.N., J. Org. Chem., 1977, 42, 1073.
- (1977) J. Org. Chem. , vol.42 , pp. 1073
- Brown, H.C.¹ Ravindranathan, M.² Peters, E.N.³

47
- 85023244407
- Moore, W.R.; Starks, C.M. To be published.
- Moore, W.R.¹ Starks, C.M.²

48
- 85022631642
- Hammond, G.S., J. Am. Chem. Soc., 1964, 86, 1957.
- (1964) J. Am. Chem. Soc. , vol.86 , pp. 1957
- Hammond, G.S.¹

49
- 33947460727
- Fainberg, A.H.; Winstein, S., J. Am. Chem. Soc., 1956, 78, 2770.
- (1956) J. Am. Chem. Soc. , vol.78 , pp. 2770
- Fainberg, A.H.¹ Winstein, S.²

50
- 85023243415
- Almeningen, A.; Bastiansen, O.S.K.R., K. Nor. Vidensk., 1968.
- (1968) K. Nor. Vidensk.
- Almeningen, A.¹ Bastiansen, O.S.K.R.²

51
- 84943847258
- Dutton, L.F., Ed., Chem. Soc., 1958.
- (1958) Chem. Soc.
- Dutton, L.F.¹

52
- 0011635292
- Dhar. J., Indian J. Phys., 1932, 7, 43.
- (1932) Indian J. Phys. , vol.7 , pp. 43
- Dhar, J.¹

53
- 33750669952
- Kitaigorodsky, A., Acta Physicochim. URSS, 1946, 21, 575.
- (1946) Acta Physicochim. URSS , vol.21 , pp. 575
- Kitaigorodsky, A.¹

54
- 84943974390
- Chan, J.Y.; LeFevre, C.G.; LeFevre, R.J.W., J. Chem. Soc., 1959, 2666.
- (1959) J. Chem. Soc. , pp. 2666
- Chan, J.Y.¹ LeFevre, C.G.² LeFevre, R.J.W.³

55
- 0001401349
- Bastiansen, O., Acta Chem. Scand., 1949, 3, 408.
- (1949) Acta Chem. Scand. , vol.3 , pp. 408
- Bastiansen, O.¹

56
- 0000703879
- Bastiansen, O., Acta Chem. Scand., 1950, 4, 926.
- (1950) Acta Chem. Scand. , vol.4 , pp. 926
- Bastiansen, O.¹

57
- 8344224100
- Bastiansen, O., Acta Chem. Scand., 1952, 6, 205.
- (1952) Acta Chem. Scand. , vol.6 , pp. 205
- Bastiansen, O.¹

58
- 0003182008
- Bastiansen, O.; Smedvik, L., Acta Chem. Scand., 1954, 9, 1593.
- (1954) Acta Chem. Scand. , vol.9 , pp. 1593
- Bastiansen, O.¹ Smedvik, L.²

59
- 33644765544
- Maier, J.P.; Turner, D.W., Faraday Discuss. Chem. Soc., 1972, 54, 149.
- (1972) Faraday Discuss. Chem. Soc. , vol.54 , pp. 149
- Maier, J.P.¹ Turner, D.W.²

60
- 85023243834
- Kekule Symposium, Butterworths: London
- Coulson, C.A. “Theoretical Organic Chemistry”, Kekule Symposium, Butterworths: London, 1959, p 57.
- (1959) Theoretical Organic Chemistry , pp. 57
- Coulson, C.A.¹

61
- 37049044720
- Howlett, K.E., J. Chem. Soc., 1960, 1055.
- (1960) J. Chem. Soc. , pp. 1055
- Howlett, K.E.¹

62
- 0043054014
- Burns, D.M.; Iball, J., Proc. R. Soc. London, 1955, 227, 200.
- (1955) Proc. R. Soc. London , vol.227 , pp. 200
- Burns, D.M.¹ Iball, J.²

63
- 3142582759
- Jones, R.N., J. Am. Chem. Soc., 1941, 64, 1658.
- (1941) J. Am. Chem. Soc. , vol.64 , pp. 1658
- Jones, R.N.¹

64
- 37049064874
- Braude, E.A.; Forbes, W.F., J. Chem. Soc., 1955, 3776.
- (1955) J. Chem. Soc. , pp. 3776
- Braude, E.A.¹ Forbes, W.F.²

65
- 0002656039
- IJnanue, A.; Bothorel, P., Bull. Soc. Chim. Fr., 1966, 1640.
- (1966) Bull. Soc. Chim. Fr. , pp. 1640
- IJnanue, A.¹ Bothorel, P.²

66
- 37049040855
- Beaven, G.H.; Bird, G.R.; Hall, D.M.; Johnson, E.A.; Ladbury, J.E.; Lesslie, M.S.; Turner, E.E., J. Chem. Soc., 1955, 2708.
- (1955) J. Chem. Soc. , pp. 2708
- Beaven, G.H.¹ Bird, G.R.² Hall, D.M.³ Johnson, E.A.⁴ Ladbury, J.E.⁵ Lesslie, M.S.⁶ Turner, E.E.⁷

67
- 33947089410
- Nelson, G.L.; Levy, G.C.; Cargioli, J.D., J. Am. Chem. Soc., 1972, 94, 3089.
- (1972) J. Am. Chem. Soc. , vol.94 , pp. 3089
- Nelson, G.L.¹ Levy, G.C.² Cargioli, J.D.³

68
- 0000722412
- Olah, G.A.; Westerman, P.W.; Nishimura, J., J. Am. Chem. Soc., 1974, 96, 3548.
- (1974) J. Am. Chem. Soc. , vol.96 , pp. 3548
- Olah, G.A.¹ Westerman, P.W.² Nishimura, J.³

69
- 0001305725
- Olah, G.A.; Westerman, P.W.; Forsyth, D.A.; J. Am. Chem. Soc., 1975, 97, 3419.
- (1975) J. Am. Chem. Soc. , vol.97 , pp. 3419
- Olah, G.A.¹ Westerman, P.W.² Forsyth, D.A.³

70
- 0009221849
- Spieseke, H.; Schneider, W.G., J. Chem. Phys., 1961, 35, 731.
- (1961) J. Chem. Phys. , vol.35 , pp. 731
- Spieseke, H.¹ Schneider, W.G.²

71
- 77956756062
- Farnum, D.G., Adv. Phys. Org. Chem., 1975, 11, 123.
- (1975) Adv. Phys. Org. Chem. , vol.11 , pp. 123
- Farnum, D.G.¹

72
- 0000251751
- Olah, G.A.; White, A.M., J. Am. Chem. Soc., 1969, 91, 5801.
- (1969) J. Am. Chem. Soc. , vol.91 , pp. 5801
- Olah, G.A.¹ White, A.M.²

73
- 0000182557
- Olah, G.A.; Spear, R.J., J. Am. Chem. Soc., 1975, 97, 1539.
- (1975) J. Am. Chem. Soc. , vol.97 , pp. 1539
- Olah, G.A.¹ Spear, R.J.²

74
- 0001078928
- Wolf, J.F.; Harch, P.G.; Taft, R.W.E.; Hehre, W.J., J. Am. Chem. Soc., 1975, 97, 2902.
- (1975) J. Am. Chem. Soc. , vol.97 , pp. 2902
- Wolf, J.F.¹ Harch, P.G.² Taft, R.W.E.³ Hehre, W.J.⁴

75
- 0005101569
- Olah, G.A.; Jeuell, C.L.; White, A.M., J. Am. Chem. Soc., 1969, 91, 3961.
- (1969) J. Am. Chem. Soc. , vol.91 , pp. 3961
- Olah, G.A.¹ Jeuell, C.L.² White, A.M.³

76
- 0001678180
- Dewar, M.J.S., J. Am. Chem. Soc., 1952, 74, 3345.
- (1952) J. Am. Chem. Soc. , vol.74 , pp. 3345
- Dewar, M.J.S.¹

77
- 0000935158
- Brown, H.C.; Okamoto, Y., J. Am. Chem. Soc., 1957, 79, 1913.
- (1957) J. Am. Chem. Soc. , vol.79 , pp. 1913
- Brown, H.C.¹ Okamoto, Y.²

78
- 0000144654
- Cagle, R.W.; Eyring, H., J. Am. Chem. Soc., 1951, 73, 5628.
- (1951) J. Am. Chem. Soc. , vol.73 , pp. 5628
- Cagle, R.W.¹ Eyring, H.²

79
- 77955754333
- Klages, F., Chem. Ber., 1949, 82, 358.
- (1949) Chem. Ber. , vol.82 , pp. 358
- Klages, F.¹

80
- 85023242908
- Ed., Wiley: New York
- In “Steric Effects in Organic Chemistry”, Newman, M.S., Ed., Wiley: New York, 1956; pp 481-484.
- (1956) Steric Effects in Organic Chemistry , pp. 481-484
- Newman, M.S.¹

81
- 33947444036
- Mowry, D.T.; Dazzi, J.; Renoll, M.; Shortridge, R.W., J. Am. Chem. Soc., 1948, 70, 1916.
- (1948) J. Am. Chem. Soc. , vol.70 , pp. 1916
- Mowry, D.T.¹ Dazzi, J.² Renoll, M.³ Shortridge, R.W.⁴

82
- 0006696315
- Wiley: New York
- Ray, F.E.; Rieveschl, G., Jr. “Organic Syntheses”, Collect. Vol. 3, Wiley: New York, 1955; p 23.
- (1955) Organic Syntheses , pp. 23
- Ray, F.E.¹ Rieveschl, G.²

83
- 8344289481
- Burger, A.; Mosettig, E., J. Am. Chem. Soc., 1936, 58, 1857.
- (1936) J. Am. Chem. Soc. , vol.58 , pp. 1857
- Burger, A.¹ Mosettig, E.²

84
- 2142685290
- Rapoport, H.; Williams, A.R., J. Am. Chem. Soc., 1949, 71, 1774.
- (1949) J. Am. Chem. Soc. , vol.71 , pp. 1774
- Rapoport, H.¹ Williams, A.R.²

85
- 84987012345
- Maquestian, A.; Van Haverbeke, Y.; Delalien, F., Org. Mass Spectrom., 1971, 5, 1015.
- (1971) Org. Mass Spectrom. , vol.5 , pp. 1015
- Maquestian, A.¹ Van Haverbeke, Y.² Delalien, F.³

86
- 33847799430
- Ohkata, K., J. Org. Chem., 1976, 41, 2162.
- (1976) J. Org. Chem. , vol.41 , pp. 2162
- Ohkata, K.¹

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