Ir-Catalyzed Allylic Amination/Ring-Closing Metathesis:  A New Route to Enantioselective Synthesis of Cyclic β-Amino Alcohol Derivatives

2007 ◽  
Vol 72 (19) ◽  
pp. 7443-7446 ◽  
Author(s):  
Jun Hee Lee ◽  
Seunghoon Shin ◽  
Jahyo Kang ◽  
Sang-gi Lee
Keyword(s):  
Amino Alcohol ◽  
Enantioselective Synthesis ◽  
Allylic Amination ◽  
Ring Closing Metathesis

scholarly journals Enantioselective Synthesis of the Ethyl Analog of the Marine Alkaloid Haliclorensin C

Molecules ◽  
2019 ◽  
Vol 24 (6) ◽  
pp. 1069
Author(s):  
Guillaume Guignard ◽  
Núria Llor ◽  
David Pubill ◽  
Joan Bosch ◽  
Mercedes Amat
Keyword(s):  
Building Block ◽  
Amino Alcohol ◽  
Ring Opening ◽  
Enantioselective Synthesis ◽  
Ring Closing Metathesis ◽  
Biological Screening ◽  
Marine Alkaloid ◽  
Key Steps

The enantioselective synthesis (3.7% overall yield in nine steps from 2) and biological screening of the ethyl analog of the macrocyclic marine alkaloid haliclorensin C (compound 5) are reported. Amino alcohol 3, generated by a LiNH2BH3-promoted reductive ring-opening/debenzylation sequence from phenylglycinol-derived lactam 2, was used as the starting chiral linear building block. Incorporation of the undecene chain via the nosyl derivative 12, methylenation of the pentanol moiety, and a ring-closing metathesis are the key steps of the synthesis.

ChemInform Abstract: Enantioselective Synthesis of Bicyclic Compounds via Catalytic 1,4-Addition-Ring Closing Metathesis.

ChemInform ◽  
2010 ◽  
Vol 32 (33) ◽  
pp. no-no
Author(s):  
Robert Naasz ◽  
Leggy A. Arnold ◽  
Adriaan J. Minnaard ◽  
Ben L. Feringa
Keyword(s):  
Enantioselective Synthesis ◽  
Ring Closing Metathesis ◽  
Bicyclic Compounds

A Double Ring Closing Metathesis Reaction in the Rapid, Enantioselective Synthesis of NK-1 Receptor Antagonists

2001 ◽  
Vol 3 (5) ◽  
pp. 671-674 ◽  
Author(s):  
Debra J. Wallace ◽  
Jonathan M. Goodman ◽  
Derek J. Kennedy ◽  
Antony J. Davies ◽  
Cameron J. Cowden ◽  
...  
Keyword(s):  
Enantioselective Synthesis ◽  
Metathesis Reaction ◽  
Receptor Antagonists ◽  
Ring Closing Metathesis ◽  
Double Ring

Enantioselective synthesis of α,α-difluoro-β-lactams using amino alcohol ligands

2014 ◽  
Vol 12 (33) ◽  
pp. 6484-6489 ◽  
Author(s):  
Atsushi Tarui ◽  
Takeshi Ikebata ◽  
Kazuyuki Sato ◽  
Masaaki Omote ◽  
Akira Ando
Keyword(s):  
Amino Alcohol ◽  
Enantioselective Synthesis ◽  
Reformatsky Reaction

A practical and highly enantioselective Reformatsky reaction of ethyl bromodifluoroacetate with imines using a cheap and commercially available amino alcohol ligand is described.

The Fürstner Synthesis of Amphidinolide F

2017 ◽  
Author(s):  
Douglass F. Taber
Keyword(s):  
Amino Alcohol ◽  
Aldol Condensation ◽  
Free Acid ◽  
The Other ◽  
Unsaturated Ester ◽  
Alkyne Metathesis ◽  
Max Planck ◽  
Ring Closing Metathesis ◽  
Enantiomerically Pure ◽  
Metathesis Catalyst

The amphidinolides, having zero, one, or (as exemplified by amphidinolide F 3) two tetrahydrofuran rings, have shown interesting antineoplastic activity. It is a tribute to his development of robust Mo catalysts for alkyne metathesis that Alois Fürstner of the Max-Planck-Institut für Kohlenforschung Mülheim could with confidence design (Angew. Chem. Int. Ed. 2013, 52, 9534) a route to 3 that relied on the ring-closing metathesis of 1 to 2 very late in the synthesis. Three components were prepared for the assembly of 1. Julia had already reported (J. Organomet. Chem. 1989, 379, 201) the preparation of the E bromodiene 5 from the sulfone 4. The alcohol 7 was available by the opening of the enantiomerically-pure epoxide 6 with propynyl lithium, followed by oxidation following the Pagenkopf pro­tocol. Amino alcohol-directed addition of the organozinc derived from 5 to the alde­hyde from oxidation of 7 completed the assembly of 8. Addition of the enantiomer 10 of the Marshall butynyl reagent to 9 followed by protection, oxidation to 11, and addition of, conveniently, the other Marshall enan­tiomer 12 led to the protected diol 13. Silylcupration–methylation of the free alkyne set the stage for selective desilylation and methylation of the other alkyne. Iodination then completed the trisubstituted alkene of 14. Methylation of the crystalline lactone 15, readily prepared from D-glutamic acid, led to a mixture of diastereomers. Deprotonation of that product followed by an aque­ous quench delivered 16. Reduction followed by reaction with the phosphorane 17 gave the unsaturated ester, that cyclized with TBAF to the crystalline 18. The last ste­reogenic center of 22 was established by proline-mediated aldol condensation of the aldehyde 19 with the ketone 20. To assemble the three fragments, the ketone of 21 was converted to the enol triflate and thence to the alkenyl stannane. Saponification gave the free acid 22, that was acti­vated, then esterified with the alcohol 18. Coupling of the stannane with the iodide 14 followed by removal of the TES group led to the desired diyne 1. It is noteworthy that the Mo metathesis catalyst is stable enough to tolerate the free alcohol of 1 in the cyclization to 2.

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