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Tjeng AA, Handore KL, Batey RA. Stereocontrolled Microwave-Assisted Domino [3,3]-Sigmatropic Reactions: A Winstein-Overman Rearrangement for the Formation of Differentiated Contiguous C-N Bonds. Org Lett 2020; 22:3050-3055. [PMID: 32223252 DOI: 10.1021/acs.orglett.0c00801] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
A domino [3,3]-sigmatropic rearrangement sequence employing a sequential reversible allylic azide rearrangement followed by an irreversible Overman reaction provides a new route to the formation of two contiguous C-N bonds. The reaction occurs in a stereocontrolled fashion in two steps from readily available alkenyl epoxides via initial azide anion ring opening of the epoxides.
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Affiliation(s)
- Andy A Tjeng
- Davenport Research Laboratories, Dept. of Chemistry, University of Toronto, 80 St. George St., Toronto, ON, M5S 3H6, Canada
| | - Kishor L Handore
- Davenport Research Laboratories, Dept. of Chemistry, University of Toronto, 80 St. George St., Toronto, ON, M5S 3H6, Canada
| | - Robert A Batey
- Davenport Research Laboratories, Dept. of Chemistry, University of Toronto, 80 St. George St., Toronto, ON, M5S 3H6, Canada
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2
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Synthesis of enantiomerically pure enones (2-benzyloxypyran-3-ones) derived from pentoses. Carbohydr Res 2019; 479:31-40. [DOI: 10.1016/j.carres.2019.05.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2019] [Revised: 05/02/2019] [Accepted: 05/15/2019] [Indexed: 01/19/2023]
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3
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Kang HY, Kang YK. Allylic Azide Rearrangements Investigated by Density Functional Theory Calculations. B KOREAN CHEM SOC 2017. [DOI: 10.1002/bkcs.11318] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Han-Young Kang
- Department of Chemistry; Chungbuk National University; Cheongju Chungbuk, 28644 Korea
| | - Young Kee Kang
- Department of Chemistry; Chungbuk National University; Cheongju Chungbuk, 28644 Korea
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4
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Lee SJ, Yang HW, Han TH, Yoon CM. Synthesis of Aryl-( E)-2-(azidomethyl)alkenoate and Aryl-( Z)-2-(azidomethyl)acrylonitrile from Aryl Aldehydes and Activated Alkenes via One-Pot Way. B KOREAN CHEM SOC 2016. [DOI: 10.1002/bkcs.10751] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Sang-Jin Lee
- Department of Advanced Material Chemistry; Korea University; Sejong-si, 339-770 South Korea
| | - Hae-Won Yang
- Department of Advanced Material Chemistry; Korea University; Sejong-si, 339-770 South Korea
| | - Tae-Hwi Han
- Department of Advanced Material Chemistry; Korea University; Sejong-si, 339-770 South Korea
| | - Cheol Min Yoon
- Department of Advanced Material Chemistry; Korea University; Sejong-si, 339-770 South Korea
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5
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Kubiak A, Kołodziuk R, Porwański S, Zawisza A. Palladium(0)-catalysed synthesis of 2,3- and 3,4-unsaturated aryl β-O-glycosides. Carbohydr Res 2015; 417:34-40. [DOI: 10.1016/j.carres.2015.08.016] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2015] [Revised: 08/26/2015] [Accepted: 08/28/2015] [Indexed: 01/13/2023]
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6
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Shankaraiah G, Vijaya Kumar T, Venkateswara Reddy G, Madhusudana Rao J, Suresh Babu K. Stereoselective Synthesis of (−)-Pinidinone. Helv Chim Acta 2013. [DOI: 10.1002/hlca.201200338] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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7
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Ding F, William R, Liu XW. Ferrier-Type N-Glycosylation: Synthesis of N-Glycosides of Enone Sugars. J Org Chem 2013; 78:1293-9. [PMID: 23289793 DOI: 10.1021/jo302619b] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Feiqing Ding
- Division
of Chemistry and Biological Chemistry, School of Physical and Mathematical
Sciences, Nanyang Technological University, 21 Nanyang Link, Singapore 637371
| | - Ronny William
- Division
of Chemistry and Biological Chemistry, School of Physical and Mathematical
Sciences, Nanyang Technological University, 21 Nanyang Link, Singapore 637371
| | - Xue-Wei Liu
- Division
of Chemistry and Biological Chemistry, School of Physical and Mathematical
Sciences, Nanyang Technological University, 21 Nanyang Link, Singapore 637371
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8
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Baldoni L, Marino C. Synthesis of S- and C-galactofuranosides via a galactofuranosyl iodide. Isolable 1-galactofuranosylthiol derivative as a new glycosyl donor. Carbohydr Res 2012; 362:70-8. [DOI: 10.1016/j.carres.2012.08.021] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2012] [Revised: 08/26/2012] [Accepted: 08/27/2012] [Indexed: 12/12/2022]
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9
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Cumpstey I, Frigell J, Pershagen E, Akhtar T, Moreno-Clavijo E, Robina I, Alonzi DS, Butters TD. Amine-linked diglycosides: Synthesis facilitated by the enhanced reactivity of allylic electrophiles, and glycosidase inhibition assays. Beilstein J Org Chem 2011; 7:1115-23. [PMID: 21915215 PMCID: PMC3169339 DOI: 10.3762/bjoc.7.128] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2011] [Accepted: 07/25/2011] [Indexed: 11/23/2022] Open
Abstract
Diglycose derivatives, consisting of two monosaccharides linked at non-anomeric positions by a bridging nitrogen atom, have been synthesised. Conversion of one of the precursor monosaccharide coupling components into an unsaturated derivative enhances its electrophilicity at the allylic position, facilitating coupling reactions. Mitsunobu coupling between nosylamides and 2,3-unsaturated-4-alcohols gave the 4-amino-pseudodisaccharides with inversion of configuration as single regio- and diastereoisomers. A palladium-catalysed coupling between an amine and a 2,3-unsaturated 4-trichloroacetimidate gave a 2-amino-pseudodisaccharide as the major product, along with other minor products. Derivatisation of the C=C double bond in pseudodisaccharides allowed the formation of Man(N4–6)Glc and Man(N4–6)Man diglycosides. The amine-linked diglycosides were found to show weak glycosidase inhibitory activity.
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Affiliation(s)
- Ian Cumpstey
- Department of Organic Chemistry, The Arrhenius Laboratory, Stockholm University, 106 91 Stockholm, Sweden
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10
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Kumar RSC, Reddy GV, Babu KS, Rao JM. Stereoselective synthesis of (+)-(8R,8aR)-perhydro-8-indolizidinol. Tetrahedron Lett 2011. [DOI: 10.1016/j.tetlet.2011.05.102] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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11
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Enantiospecific synthesis of the sugar amino acid (2S,5S)-5-(aminomethyl)-tetrahydrofuran-2-carboxylic acid. ACTA ACUST UNITED AC 2010. [DOI: 10.1016/j.tetasy.2010.08.013] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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12
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Surendra Reddy P, Ravi V, Sreedhar B. Efficient synthesis of allylic azides and one-pot regioselective synthesis of 1,4-disubstituted 1,2,3-triazoles from homoallyl alcohols. Tetrahedron Lett 2010. [DOI: 10.1016/j.tetlet.2010.05.097] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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13
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Sateesh Chandra Kumar R, Venkateswar Reddy G, Shankaraiah G, Suresh Babu K, Madhusudana Rao J. Stereoselective synthesis of dendrobate alkaloid (+)-241D and its C-4 epimer. Tetrahedron Lett 2010. [DOI: 10.1016/j.tetlet.2009.12.111] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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14
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Sateesh Chandra Kumar R, Sreedhar E, Venkateswar Reddy G, Suresh Babu K, Madhusudana Rao J. A simple and efficient enantioselective route to 2,6-disubstituted piperidines: synthesis of (2R,6S)-isosolenopsin A and (2S,6R)-isosolenopsin. ACTA ACUST UNITED AC 2009. [DOI: 10.1016/j.tetasy.2009.03.030] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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15
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Manzano VE, Uhrig ML, Varela O. Straightforward synthesis of thiodisaccharides by ring-opening of sugar epoxides. J Org Chem 2008; 73:7224-35. [PMID: 18717587 DOI: 10.1021/jo8012397] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
3,4-Anhydro hexopyranosides have been prepared by diastereoselective epoxidation of derivatives of 2-propyl 3,4-dideoxy-alpha-D-erythro-hex-3-enopyranoside (5), selectively protected at HO-2 and HO-6. The allylic group at C-2, in 5 and derivatives, plays a critical role in the facial selectivity of the epoxidation reaction. Thus, the free HO-2 in 3 (the 6-O-acetyl derivative of 5) directs the attack of m-chloroperbenzoic acid from the more hindered alpha face of the molecule to give 2-propyl 6-O-acetyl-3,4-anhydro-alpha-D-allopyranoside (7) accompanied by the beta epoxide 6 as a very minor product. Reverse diastereoselectivity has been obtained when the HO-2 in 3 was substituted by a bulky tert-butyldimethylsilyl (TBS) group. In this case, the major isomer was the 2-O-TBS derivative of 6 (alpha-D-galacto configuration). The ring-opening of sugar epoxides by nucleophilic per-O-acetyl-1-thio-beta-D-glucopyranose (11) was employed as a convenient approach to the synthesis of (1-->3)- and (1-->4)-thiodisaccharides. For example, ring-opening of the oxirane 7 by 11 led to the expected regioisomeric per-O-acetyl thiodisaccharides beta-D-Glc-S-(1-->3)-4-thio-alpha-D-Glc-O-iPr (12) and beta-D-Glc-S-(1-->4)-4-thio-alpha-D-Gul-O-iPr (13). Regioselectivity in the construction of the (1-->4)-thioglycosidic linkage could be achieved by hindering C-3 of the 3,4-anhydro sugar with a bulky silyloxy group at the vicinal C-2. For instance, coupling of the 2-O-TBS derivative of 7 with 11 led regioselectively to the protected thiodisaccharide beta-D-Glc-S-(1-->4)-4-thio-alpha-D-Glc-O-iPr (27). The utility of the approach was demonstrated through the synthesis of sulfur-linked analogues of naturally occurring (laminarabiose and cellobiose) and non-natural disaccharides (i.e., beta-D-Glc-(1-->4)-alpha-D-Gul).
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Affiliation(s)
- Verónica E Manzano
- CIHIDECAR-CONICET, Departamento de Química Orgánica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Argentina
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16
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Lauzon S, Tremblay F, Gagnon D, Godbout C, Chabot C, Mercier-Shanks C, Perreault S, DeSève H, Spino C. Sterically Biased 3,3-Sigmatropic Rearrangement of Chiral Allylic Azides: Application to the Total Syntheses of Alkaloids. J Org Chem 2008; 73:6239-50. [DOI: 10.1021/jo800817p] [Citation(s) in RCA: 76] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Sophie Lauzon
- Université de Sherbrooke, Département de Chimie, 2500 Boulevard Université, Sherbrooke, Quebec, Canada, J1K 2R1
| | - François Tremblay
- Université de Sherbrooke, Département de Chimie, 2500 Boulevard Université, Sherbrooke, Quebec, Canada, J1K 2R1
| | - David Gagnon
- Université de Sherbrooke, Département de Chimie, 2500 Boulevard Université, Sherbrooke, Quebec, Canada, J1K 2R1
| | - Cédrickx Godbout
- Université de Sherbrooke, Département de Chimie, 2500 Boulevard Université, Sherbrooke, Quebec, Canada, J1K 2R1
| | - Christine Chabot
- Université de Sherbrooke, Département de Chimie, 2500 Boulevard Université, Sherbrooke, Quebec, Canada, J1K 2R1
| | - Catherine Mercier-Shanks
- Université de Sherbrooke, Département de Chimie, 2500 Boulevard Université, Sherbrooke, Quebec, Canada, J1K 2R1
| | - Stéphane Perreault
- Université de Sherbrooke, Département de Chimie, 2500 Boulevard Université, Sherbrooke, Quebec, Canada, J1K 2R1
| | - Hélène DeSève
- Université de Sherbrooke, Département de Chimie, 2500 Boulevard Université, Sherbrooke, Quebec, Canada, J1K 2R1
| | - Claude Spino
- Université de Sherbrooke, Département de Chimie, 2500 Boulevard Université, Sherbrooke, Quebec, Canada, J1K 2R1
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17
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Fast and efficient preparation of Baylis–Hillman-derived (E)-allylic azides and related compounds in aqueous medium. Tetrahedron 2006. [DOI: 10.1016/j.tet.2006.09.059] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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18
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19
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Uhrig ML, Manzano VE, Varela O. Stereoselective Synthesis of 3-Deoxy-4-S-(1→4)-Thiodisaccharides and Their Inhibitory Activities Towards β-Glycoside Hydrolases. European J Org Chem 2006. [DOI: 10.1002/ejoc.200500457] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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20
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Gagnon D, Lauzon S, Godbout C, Spino C. Sterically Biased 3,3-Sigmatropic Rearrangement of Azides: Efficient Preparation of Nonracemic α-Amino Acids and Heterocycles. Org Lett 2005; 7:4769-71. [PMID: 16209531 DOI: 10.1021/ol052034n] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
[reaction: see text] Homochiral alpha-amino acids, heterocycles, and carbocycles are efficiently constructed via a short sequence of reactions starting from the chiral auxiliary p-menthane-3-carboxaldehyde. The key feature of the sequence is a highly selective tandem Mitsunobu/3,3-sigmatropic rearrangement of hydrazoic acid that procures enantiomerically enriched allylic azides. The sequence is either terminated by oxidative cleavage to provide amino acids or by ring-closing metathesis to provide heterocycles or carbocycles bearing nitrogen.
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Affiliation(s)
- David Gagnon
- Département de Chimie, Université de Sherbrooke, Sherbrooke, QC, Canada J1K 2R1
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21
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Enantiomerically pure Diels–Alder cycloadducts from aldohexose-derived dihydropyranones. ACTA ACUST UNITED AC 2004. [DOI: 10.1016/j.tetasy.2004.08.005] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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22
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Uhrig ML, Varela O. Synthesis of glycosides of 3-deoxy-4-thiopentopyranosid-2-uloses and their reduction products: 3-deoxy-4-thiopentopyranosides. Carbohydr Res 2002; 337:2069-76. [PMID: 12433472 DOI: 10.1016/s0008-6215(02)00292-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Michael addition of common thiols to the enone system of (2S)-2-benzyloxy-2H-pyran-3(6H)-one (1) afforded the corresponding 3-deoxy-4-thiopentopyranosid-2-ulose derivatives (2-4). The reaction was highly diastereoselective, and the addition was governed by the quasiaxially disposed 2-benzyloxy substituent of the starting pyranone. As expected from the enantiomeric excess of 1 (ee > 86%) the corresponding thiouloses 2-4 exhibited the same optical purity. However, the enantiomerically pure thioulose 5 was obtained by reaction of 1 with the chiral thiol, N-(tert-butoxycarbonyl)-L-cysteine methyl ester. The thio derivative 7 was also synthesized by reaction of 6 (enantiomer of 1) with the same chiral thiol. Alternatively, 4-thiopent-2-uloses 9-12 were prepared in high optical purity by 1,4-addition of thiols to (2S)-[(S)-2'-octyloxy]dihydropyranone 8. Similarly, reaction of 13 (enantiomer of 8) with benzenemethanethiol afforded 14 (enantiomer of 10). This way, the stereocontrol exerted by the anomeric center on the starting dihydropyranone led to 4-thiopentuloses of the D and L series. Sodium borohydride reduction of the carbonyl function of uloses 10 and 12 gave the corresponding 3-deoxy-4-thiopentopyranosid-2-uloses (16-19). The diastereomers having the beta-D-threo configuration (16, 18) slightly predominated over the beta-D-erythro (17, 19) analogues. However, the reduction of the enantiomeric pyranones 10 and 14 with K-Selectride was highly diastereofacial selective in favor of the beta-D- and beta-L-threo isomers 16 and 20, respectively.
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Affiliation(s)
- María Laura Uhrig
- CIHIDECAR-CONICET, Departamento de Química Orgánica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Pabellón II, Ciudad Universitaria, 1428, Buenos Aires, Argentina
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Iriarte Capaccio CA, Varela O. Stereocontrolled diels-alder cycloadditions of sugar-derived dihydropyranones with dienes. J Org Chem 2002; 67:7839-46. [PMID: 12398511 DOI: 10.1021/jo020309w] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
2-Acetoxy-3,4-di-O-acetyl-D-arabinal (6), similar to its D-xylo analogue 4, reacted with benzyl alcohol by the tin(IV) chloride-promoted glycosylation to produce optically active (S)-2-benzyloxy-2H-pyran-3(6H)-one (8a). The L-arabinal derivative (5) gave 9a, the dihydropyranone enantiomer of 8a. These results indicated that the configuration of the C-4 stereocenter in the starting glycal defines the configuration of the new chiral center in the resulting dihydropyranone. The influence of other catalysts (BF(3) or iodine) employed for the glycosylation on the optical purity of the dihydropyranone was studied. Enantiomerically pure dihydropyranones 8b and 9c were obtained using chiral alcohols ((R)- and (S)-2-octanol, respectively) as glycosylating agents. Compounds 8a,b and 9a,c proved to be reactive dienophiles in thermal and Lewis acid-promoted Diels-Alder reactions. The addition of 2,3-dimethylbutadiene, cyclopentadiene, and 1,3-cyclohexadiene to the beta-pyranones 8a,b led to the corresponding adducts 10a,b, 12a,b, and 16a,b as major products. Enantiomeric cycloadducts were synthesized from the alpha-pyranones 9a,c. The main products were formed by highly facial-diastereoselective addition of dienes to the pyranone ring, guided by the sterical hindrance of the alkoxy substituent of the C-2 stereocenter. As cycloadditions with cycloalkadienes were also highly endo diastereoselective, these reactions gave access to pure tetrahydrobenzopyranones that carry a multitude of stereogenic centers installed in a predictable way.
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Affiliation(s)
- Christian A Iriarte Capaccio
- CIHIDECAR-CONICET, Departamento de Química Orgánica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Pabellón 2-Ciudad Universitaria, Argentina
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Capaccio CA, Varela O. Synthesis of optically active 2-alkoxy-2H-pyran-3(6H)-ones. Their use as dienophiles in Diels-Alder cycloadditions. J Org Chem 2001; 66:8859-66. [PMID: 11749616 DOI: 10.1021/jo0106896] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Optically active 2-alkoxy-2H-pyran-3(6H)-ones (4a-d) were synthesized in one step by the tin(IV) chloride-promoted glycosylation and rearrangement of the 2-acetoxy-3,4-di-O-acetyl-D-xylal (3) prepared from D-xylose (1). The absolute configuration of the new stereocenter at C-2 was determined by chemical transformation of the dihydropyranones 4a and 4b into the known alkyl pentopyranosides (7a and 7b, respectively). Also, from (1)H NMR experiments using a chiral ytterbium shift reagent, the enantiomeric excesses for 4a (>86%) and 4b (>77%) were established. Enantiomerically pure 4c and 4d were obtained by reaction of 3 with chiral 2-octanol (R and S, respectively). Dihydropyranones 4a-d were employed as dienophiles in Diels-Alder cycloadditions with 2,3-dimethylbutadiene and butadiene. Under thermal conditions, only moderate yields (approximately 50%) of cycloadducts 9a-c and 10a were respectively obtained with good diastereofacial selectivity (>80%). Optimized Lewis acid promoted cycloadditions led to 9a-d and 10a,c in higher yields (approximately 80%) and with higher diastereoselectivities (>94%). The major products were formed by approach of the dienes from the less hindered face of the dihydropyranones, and the minor products (such as 11a) were formed by addition from the opposite side. Furthermore, cycloadduct 9a was stable in an alkaline solution, whereas 11a underwent epimerization under the same conditions.
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Affiliation(s)
- C A Capaccio
- CIHIDECAR-CONICET, Departamento de Química Orgánica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, Pabellón 2, 1428, Buenos Aires, Argentina
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Steric constraints against [3,3]-sigmatropic rearrangement of allylic azides. A convenient approach to β-l-4-aminopent-2-enoglyceropyranosides. ACTA ACUST UNITED AC 2001. [DOI: 10.1016/s0957-4166(01)00450-5] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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