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Angewandte Chemie - International Edition

Volumn 46, Issue 39, 2007, Pages 7491-7494

Lithiated carbamates: Chiral carbenoids for iterative homologation of boranes and boronic esters

(4) Stymiest, Jake L a Dutheuil, Guillaume a Mahmood, Adeem a Aggarwal, Varinder K a

a UNIVERSITY OF BRISTOL (United Kingdom)

Author keywords

Asymmetric synthesis; Boranes; Boronic esters; Chiral carbenoids; Homologation

Indexed keywords

BORON COMPOUNDS; REACTION KINETICS; SUBSTRATES; SYNTHESIS (CHEMICAL);

ASYMMETRIC SYNTHESIS; BORANES; BORONIC ESTERS; CHIRAL CARBENOIDS; HOMOLOGATION;

ESTERS;

EID: 35048834773 PISSN: 14337851 EISSN: None Source Type: Journal
DOI: 10.1002/anie.200702146 Document Type: Article

Times cited : (182)

References (43)

1
- 0000122303
- a) D. S. Matteson, D. Majumder, J. Am. Chem. Soc. 1980, 102, 7588;
- (1980) J. Am. Chem. Soc , vol.102 , pp. 7588
- Matteson, D.S.¹ Majumder, D.²

2
- 33847087715
- b) D. S. Mattéson, D. Ray, J. Am. Chem. Soc. 1980, 102, 7590;
- (1980) J. Am. Chem. Soc , vol.102 , pp. 7590
- Mattéson, D.S.¹ Ray, D.²

3
- 0001163364
- For reviews on the use of boronic esters in asymmetric syntheses, see: c
- For reviews on the use of boronic esters in asymmetric syntheses, see: c) D. S. Matteson, Tetrahedron 1989, 45, 1859;
- (1989) Tetrahedron , vol.45 , pp. 1859
- Matteson, D.S.¹

4
- 35048827266
- d) D. S. Matteson, Tetrahedron 1998, 54, 1055.
- (1998) Tetrahedron , vol.54 , pp. 1055
- Matteson, D.S.¹

5
- 0001726810
- D. S. Matteson, H.-W. Man, J. Org. Chem. 1996, 61, 6047.
- (1996) J. Org. Chem , vol.61 , pp. 6047
- Matteson, D.S.¹ Man, H.-W.²

6
- 13644270301
- a) V. K. Aggarwal, G. Y. Fang, A. T. Schmidt, J. Am. Chem. Soc. 2005, 127, 1642;
- (2005) J. Am. Chem. Soc , vol.127 , pp. 1642
- Aggarwal, V.K.¹ Fang, G.Y.² Schmidt, A.T.³

7
- 35048817308
- b) G. Y. Fang, V. K. Aggarwal, Angew. Chem. 2007, 119, 363;
- (2007) Angew. Chem , vol.119 , pp. 363
- Fang, G.Y.¹ Aggarwal, V.K.²

8
- 33846436053
- Angew. Chem. Int. Ed. 2007, 46, 359;
- (2007) Chem. Int. Ed , vol.46 , pp. 359
- Angew¹

9
- 35048883290
- unpublished results
- c) G. Y. Fang, O. Wallner, N. di Blasio, V. K. Aggarwal, unpublished results.
- Fang, G.Y.¹ Wallner, O.² di Blasio, N.³ Aggarwal, V.K.⁴

10
- 0034665258
- a) R. W. Hoffmann, P. G. Nell, R. Leo, K. Harms, Chem. Eur. J. 2000, 6, 3359;
- (2000) Chem. Eur. J , vol.6 , pp. 3359
- Hoffmann, R.W.¹ Nell, P.G.² Leo, R.³ Harms, K.⁴

11
- 1442360812
- b) R. W. Hoffmann, Chem. Soc. Rev. 2003, 32, 225;
- (2003) Chem. Soc. Rev , vol.32 , pp. 225
- Hoffmann, R.W.¹

12
- 0030026268
- c) T. Satoh, K. Tahano, Tetrahedron 1996, 52, 2349.
- (1996) Tetrahedron , vol.52 , pp. 2349
- Satoh, T.¹ Tahano, K.²

13
- 33947430499
- P. R. Blakemore, M. S. Burge, J. Am. Chem. Soc. 2007, 129, 3068.
- (2007) J. Am. Chem. Soc , vol.129 , pp. 3068
- Blakemore, P.R.¹ Burge, M.S.²

14
- 33644783530
- P. R. Blakemore, S. P. Marsden, H. D. Vater, Org. Lett. 2006, 8, 773.
- (2006) Org. Lett , vol.8 , pp. 773
- Blakemore, P.R.¹ Marsden, S.P.² Vater, H.D.³

15
- 0001488536
- a) D. Hoppe, F. Hintze, P. Tebben, Angew. Chem. 1990, 102, 1457;
- (1990) Angew. Chem , vol.102 , pp. 1457
- Hoppe, D.¹ Hintze, F.² Tebben, P.³

16
- 0343583098
- Angew. Chem. Int. Ed. Engl. 1990, 29, 1422;
- (1990) Angew. Chem. Int. Ed. Engl , vol.29 , pp. 1422

17
- 0344799549
- For reviews on α-lithiation of carbamates, see: b
- For reviews on α-lithiation of carbamates, see: b) D. Hoppe, F. Hintze, P. Tebben, M. Paetow, H. Ahrens, J. Schwerdtfeger, P. Sommerfeld, J. Haller, W. Guarnieri, S. Kolczewksi, T. Hense, D. Hoppe, Pure Appl. Chem. 1994, 66, 1479;
- (1994) Pure Appl. Chem , vol.66 , pp. 1479
- Hoppe, D.¹ Hintze, F.² Tebben, P.³ Paetow, M.⁴ Ahrens, H.⁵ Schwerdtfeger, J.⁶ Sommerfeld, P.⁷ Haller, J.⁸ Guarnieri, W.⁹ Kolczewksi, S.¹⁰ Hense, T.¹¹ Hoppe, D.¹²

18
- 0000854142
- c) D. Hoppe, F. Hintze, Angew. Chem. 1997, 109, 2376;
- (1997) Angew. Chem , vol.109 , pp. 2376
- Hoppe, D.¹ Hintze, F.²

19
- 0030694010
- Angew. Chem. Int. Ed. Engl. 1997, 36, 2282;
- (1997) Angew. Chem. Int. Ed. Engl , vol.36 , pp. 2282

20
- 0000232576
- d) A. Basu, S. Thayumanavan, Angew. Chem. 2002, 114, 740;
- (2002) Angew. Chem , vol.114 , pp. 740
- Basu, A.¹ Thayumanavan, S.²

21
- 0036495880
- Angew. Chem. Int. Ed. 2002, 41, 716;
- (2002) Chem. Int. Ed , vol.41 , pp. 716
- Angew¹

22
- 35048822764
- D. Hoppe, F. Marr, M. Brüggemann in Organolithiums in Enantioselective Synthesis (Ed.: D. M. Hodgson), Springer, Heidelberg, 2003, pp. 61-137, and references therein;
- e) D. Hoppe, F. Marr, M. Brüggemann in Organolithiums in Enantioselective Synthesis (Ed.: D. M. Hodgson), Springer, Heidelberg, 2003, pp. 61-137, and references therein;

23
- 18844423506
- Eds, Z. Rappoport, I. Marek, Wiley, Chichester
- f) D. Hoppe, G. Christoph in The Chemistry of Organolithium Compounds (Eds.: Z. Rappoport, I. Marek), Wiley, Chichester, 2004, p. 1055.
- (2004) The Chemistry of Organolithium Compounds , pp. 1055
- Hoppe, D.¹ Christoph, G.²

24
- 8644265158
- a) E. Beckmann, V. Desai, D. Hoppe, Synlett 2004, 2275;
- (2004) Synlett , pp. 2275
- Beckmann, E.¹ Desai, V.² Hoppe, D.³

25
- 13844275009
- b) E. Beckmann, D. Hoppe, Synthesis 2005, 217;
- (2005) Synthesis , pp. 217
- Beckmann, E.¹ Hoppe, D.²

26
- 33746040068
- c) M. J. McGrath, P. O'Brien, Synthesis 2006, 2233.
- (2006) Synthesis , pp. 2233
- McGrath, M.J.¹ O'Brien, P.²

27
- 33744818526
- One isolated example of a reaction of a lithiated carbamate with an arylboronate has been reported during the total synthesis of N-acetylcolchinol: G. Besong, K. Jarowicki, P. J. Kocienski, E. Sliwinski, F. T. Boyle, Org. Biomol. Chem. 2006, 4, 2193
- One isolated example of a reaction of a lithiated carbamate with an arylboronate has been reported during the total synthesis of N-acetylcolchinol: G. Besong, K. Jarowicki, P. J. Kocienski, E. Sliwinski, F. T. Boyle, Org. Biomol. Chem. 2006, 4, 2193.

28
- 33644499757
- [3c] In fact, the only other examples where the boron substituent migrates in preference to the boracycle are cases involving a (small) halide leaving group or carbonylation. In all other cases, the boracycle migrates preferentially. Thus the large carbamate moiety is behaving as a small leaving group. For a discussion of the factors influencing the migration of groups on nonsymmetrical ate complexes of organoboranes, see: V. K. Aggarwal, G. Y. Fang, X. Ginesta, D. Howells, M. Zaja, Pure Appl. Chem. 2006, 78, 215.
- [3c] In fact, the only other examples where the boron substituent migrates in preference to the boracycle are cases involving a (small) halide leaving group or carbonylation. In all other cases, the boracycle migrates preferentially. Thus the large carbamate moiety is behaving as a small leaving group. For a discussion of the factors influencing the migration of groups on nonsymmetrical ate complexes of organoboranes, see: V. K. Aggarwal, G. Y. Fang, X. Ginesta, D. Howells, M. Zaja, Pure Appl. Chem. 2006, 78, 215.

29
- 35048902965
- We believe that this additive sequesters either, )-sparteine 12 or the carbamate leaving group 13, thus preventing it from binding to the borane 14, which otherwise results in a degree of homolysis of the benzylic carbon-boron bond, thus lowering the e.r. as seen in the absence of MgBr2 entry 4, Table 1, Chemical Equation Presented
- 2 (entry 4, Table 1). (Chemical Equation Presented)

30
- 35048904410
- Although it is possible for B-Ph-9-BBN to react with the lithiated carbamate with different enantioselectivity to other boranes, we were able to show that the difference in e.r. occurs after ate complex formation. Treatment of lithiated 1a with the mixed borane PhEt2B gave, after oxidative workup, a mixture of the two alcohols (3a and 3d) with enantiomeric ratios of 96:4 and 78:22, respectively see below, Since the two alcohols are derived from the common intermediate 15, this species must be formed with at least 96:4 e.r. Intermediate 15 undergoes stereospecific migration of Et and Ph groups leading to boranes C and D, respectively. Oxidation of borane D led to substantial loss of e.r. whilst C did not. However, boranes related to D had been generated in our sulfur ylide reactions with no loss of e.r.[3a] The difference in this case is that D is generated in the presence of agen
- 2B and oxidative workup again furnished the alcohols 3a and 3d but this time with identical e.r. values. (Chemical Equation Presented)

31
- 1942500259
- For examples, see: a
- For examples, see: a) J. M. Stoddard, K. J. Shea, Chem. Commun. 2004, 830;
- (2004) Chem. Commun , pp. 830
- Stoddard, J.M.¹ Shea, K.J.²

32
- 0037414564
- b) A. Bottoni, M. Lombardo, A. Neri, C. Trombini, J. Org. Chem. 2003, 68, 3397.
- (2003) J. Org. Chem , vol.68 , pp. 3397
- Bottoni, A.¹ Lombardo, M.² Neri, A.³ Trombini, C.⁴

33
- 35048897809
- 2 for 12 h was required to achieve 1,2-metalate rearrangement.
- 2 for 12 h was required to achieve 1,2-metalate rearrangement.

34
- 35048894696
- 11B NMR spectroscopy; the reaction was monitored beginning at -80°C and warmed up by 10°C increments every 5 min over 35 min. Rearrangement of ate complex 4 began at -40°C.
- 11B NMR spectroscopy; the reaction was monitored beginning at -80°C and warmed up by 10°C increments every 5 min over 35 min. Rearrangement of ate complex 4 began at -40°C.

35
- 0342354114
- B. D. Johnston, A. C. Oehlschlager, J. Org. Chem. 1986, 51, 760.
- (1986) J. Org. Chem , vol.51 , pp. 760
- Johnston, B.D.¹ Oehlschlager, A.C.²

36
- 0010603342
- a) H. C. Brown, M. M. Midland, A. B. Levy, J. Am. Chem. Soc. 1973, 95, 2394;
- (1973) J. Am. Chem. Soc , vol.95 , pp. 2394
- Brown, H.C.¹ Midland, M.M.² Levy, A.B.³

37
- 0041689538
- b) E. Hupe, I. Marek, P. Knochel, Org. Lett. 2002, 4, 2861.
- (2002) Org. Lett , vol.4 , pp. 2861
- Hupe, E.¹ Marek, I.² Knochel, P.³

38
- 35048860734
- 2O in pyridine.
- 2O in pyridine.

39
- 15244341482
- The enhancement of the enantiomeric ratio always occurs when two enantioselective operations are mapped onto the same substrate. In theory, if the first homologation gives an x:y. ratio of enantiomers (97-98:3-2 ratio observed for both, )-sparteine 12 and, )-11, then, assuming there is no kinetic resolution (both enantiomers of the boronic ester react at the same rate) or double stereo differentiation (the second homologation is not affected by the asymmetric center formed in the first step of the reaction, the ratio of enantiomers for the second homologation will be x 2:y2, 99.8:0.2 expected; e.r. > 98:2 observed, The enantiomeric excess of the doubly homologated product is therefore considerably increased. One can view this as the x2:y 2 rule. This process also generates the diastereomeric compound amount, 2xy; 94:6 expected; 90-96:10-4 observed, See the following for previous discussions of enantiome
- 2 rule. This process also generates the diastereomeric compound (amount = 2xy; 94:6 expected; 90-96:10-4 observed). See the following for previous discussions of enantiomeric amplification: a) E. Negishi, Dalton Trans. 2005, 827;

40
- 0000308238
- b) V. K. Aggarwal, B. N. Esquivel-Zamora, G. R. Evans, E. Jones, J. Org. Chem. 1998, 63, 7306;
- (1998) J. Org. Chem , vol.63 , pp. 7306
- Aggarwal, V.K.¹ Esquivel-Zamora, B.N.² Evans, G.R.³ Jones, E.⁴

41
- 0008080527
- c) S. E. Baba, K. Sartor, J.-C. Poulin, H. B. Kagan, Bull. Chim. Soc. Fr. 1994, 131, 525.
- (1994) Bull. Chim. Soc. Fr , vol.131 , pp. 525
- Baba, S.E.¹ Sartor, K.² Poulin, J.-C.³ Kagan, H.B.⁴

42
- 0037048610
- a) M. J. Dearden, C. R. Firkin, J-P. R. Hermet, P. O'Brien, J. Am. Chem. Soc. 2002, 124, 11870;
- (2002) J. Am. Chem. Soc , vol.124 , pp. 11870
- Dearden, M.J.¹ Firkin, C.R.² Hermet, J.-P.R.³ O'Brien, P.⁴

43
- 85026879940
- b) A. J. Dixon, M. J. McGrath, P. O'Brien, Org. Synth. 2006, 83, 141.
- (2006) Org. Synth , vol.83 , pp. 141
- Dixon, A.J.¹ McGrath, M.J.² O'Brien, P.³

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