High-Pressure-Promoted Asymmetric Aldol Reactions of Ketones with Aldehydes Catalyzed by l-Proline [1]

Abstract

High-pressure conditions were applied to direct asymmetric aldol reactions between ketones and aldehydes with l-proline as a commercially available chiral amino acid catalyst.

Key words

high-pressure - asymmetric aldol reaction - l-proline - aldehydes - ketones

References

• 1 High-Pressure Organic Chemistry. Part 26. For Part 25, see: Kumamoto K. Misawa Y. Tokita S. Kubo Y. Kotsuki H. Tetrahedron Lett.  2002,  43:  1035 
• 2a Heathcock CH. Comprehensive Organic Synthesis   Vol. 2:  Trost BM. Fleming I. Heathcock CH. Pergamon Press; Oxford: 1991.  Chap. 1.5.
• 2b Mukaiyama T. Kobayashi S. Org. React.  1994,  46:  1 
• 3a Takayama S. McGarvey G. Wong C.-H. Chem. Soc. Rev.  1997,  26:  407 
• 3b Cowden CJ. Paterson I. Org. React.  1997,  51:  1 
• 3c Nelson SG. Tetrahedron: Asymmetry  1998,  9:  357 
• 3d Gröger H. Vogl EM. Shibasaki M. Chem.-Eur. J.  1998,  4:  1137 
• 3e Carreira EM. Comprehensive Asymmetric Synthesis   Vol. 3:  Jacobsen EN. Pfaltz A. Yamamoto H. Springer-Verlag; Berlin: 1999.  Chap. 29.1.
• 3f Machajewski TD. Wong C.-H. Angew. Chem. Int. Ed.  2000,  39:  1352 
• 4a Gröger H. Wilken J. Angew. Chem. Int. Ed.  2001,  40:  529 
• 4b Dalko PI. Moisan L. Angew. Chem. Int. Ed.  2001,  40:  3726 
• 4c List B. Synlett  2001,  1675 
• 4d Palomo C. Oiarbide M. García JM. Chem.-Eur. J.  2002,  8:  36 
• 4e Alcaide B. Almendros P. Eur. J. Org. Chem.  2002,  1595 
• 4f Jarvo ER. Miller SJ. Tetrahedron  2002,  58:  2481 
• 4g List B. Tetrahedron  2002,  58:  5573 
• 4h Alcaide B. Almendros P. Angew. Chem. Int. Ed.  2003,  42:  858 
• 4i Duthaler RO. Angew. Chem. Int. Ed.  2003,  42:  975 
• 5a List B. Lerner RA. Barbas CF. J. Am. Chem. Soc.  2000,  122:  2395 
• 5b Notz W. List B. J. Am. Chem. Soc.  2000,  122:  7386 
• 5c List B. Pojarliev P. Castello C. Org. Lett.  2001,  3:  573 
• 5d Pidathala C. Hoang L. Vignola N. List B. Angew. Chem. Int. Ed.  2003,  42:  2785 
• 6a Sakthivel K. Notz W. Bui T. Barbas CF. J. Am. Chem. Soc.  2001,  123:  5260 
• 6b Chowdari NS. Ramachary DB. Córdova A. Barbas CF. Tetrahedron Lett.  2002,  43:  9591 
• 6c Córdova A. Notz W. Barbas CF. Chem. Commun.  2002,  3024 
• 6d Chowdari NS. Ramachary DB. Barbas CF. Org. Lett.  2003,  5:  1685 
• For other examples of asymmetric aldol reactions under proline catalysis, see:
• 7a Bøgevig A. Kumaragurubaran N. Jørgensen KA. Chem. Commun.  2002,  620 
• 7b Northrup AB. MacMillan DWC. J. Am. Chem. Soc.  2002,  124:  6798 
• 7c Darbre T. Machuqueiro M. Chem. Commun.  2003,  1090 
• 7d Tang Z. Jiang F. Yu L.-T. Cui X. Gong L.-Z. Mi A.-Q. Jiang Y.-Z. Wu Y.-D. J. Am. Chem. Soc.  2003,  125:  5262 
• 7e See also: Nakadai M. Saito S. Yamamoto H. Tetrahedron  2002,  58:  8167 ; and references cited therein
• For the same reason, ionic liquids were introduced as novel reaction media:
• 8a Loh T.-P. Feng L.-C. Yang H.-Y. Yang J.-Y. Tetrahedron Lett.  2002,  43:  8741 
• 8b Kotrusz P. Kmentová I. Gotov B. Toma S. Solcániová E. Chem. Commun.  2002,  2510 
• 8c See also: Peng Y.-Y. Ding Q.-P. Li Z. Wang PG. Cheng J.-P. Tetrahedron Lett.  2003,  44:  3871 
• 9 For a recent review, see: Jenner G. Tetrahedron  2002,  58:  5185 
• For some recent examples of high-pressure-promoted aldol and related reactions, see:
• 10a Desmaële D. Tetrahedron Lett.  1996,  37:  1233 
• 10b Bellassoued M. Reboul E. Dumas F. Tetrahedron Lett.  1997,  38:  5631 
• 10c Jenner G. New J. Chem.  1999,  23:  525 
• 10d Jenner G. Tetrahedron Lett.  2001,  42:  243 
• 10e Misumi Y. Bulman RA. Matsumoto K. Heterocycles  2002,  56:  599 
• 10f Misumi Y. Matsumoto K. Angew. Chem. Int. Ed.  2002,  41:  1031 
• 12 Bordwell FG. Zhang X.-M. Acc. Chem. Res.  1993,  26:  510 
• 13a Bahmanyar S. Houk KN. J. Am. Chem. Soc.  2001,  123:  11273 
• 13b Bahmanyar S. Houk KN. J. Am. Chem. Soc.  2001,  123:  12911 
• 13c Hoang L. Bahmanyar S. Houk KN. List B. J. Am. Chem. Soc.  2003,  125:  16 
• 13d Bahmanyar S. Houk KN. Org. Lett.  2003,  5:  1249 
• 13e Bahmanyar S. Houk KN. Martin HJ. List B. J. Am. Chem. Soc.  2003,  125:  2475 
• 13f See also: Arnó M. Domingo LR. Theor. Chem. Acc.  2002,  108:  232 
• 13g Rankin KN. Gauld JW. Boyd RJ. J. Phys. Chem. A  2002,  106:  5155 
• 14a Sera A. Takagi K. Katayama H. Yamada H. Matsumoto K. J. Org. Chem.  1988,  53:  1157 
• 14b Oishi T. Oguri H. Hirama M. Tetrahedron: Asymmetry  1995,  6:  1241 
• 14c Markó IE. Giles PR. Hindley NJ. Tetrahedron  1997,  53:  1015 

11

Typical Experimental Procedure for the Reaction of Acetone with Benzaldehyde (entry 2). A mixture of benzaldehyde (53 mg, 0.5 mmol) and l-proline (17 mg, 0.15 mmol) in acetone (1.5 mL) was placed in a Teflon reaction vessel and allowed to react at 0.2 GPa and r.t. for 24 h. The reaction was quenched by adding H₂O, and the mixture was extracted with CH₂Cl₂. The crude product was purified by preparative TLC (hexane/EtOAc = 2:1) to afford the desired adduct (74 mg, 90%). The ee value was determined by HPLC analysis using a Daicel Chiralpak AD column, with 1% 2-propanol in hexane as the eluent, at 0.5 mL/min.

15

According to the literature, [5a] [6a] this type of asymmetric catalysis is best performed in dry DMSO.