- Bisoxazoline and bioxazoline chiral ligands bearing 4-diphenylmethyl shielding substituents. Diels-Alder reaction of cyclopentadiene with 3-acryloyl-2-oxazolidinone catalyzed by the aqua nickel(II) complex
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Enantiopure 2-amino-3,3-diphenyl-1-propanol was synthesized by the hidantoin route starting from diphenyl-acetaldehyde followed by subsequent functional group transformations and optical resolution by a chiral HPLC. The amino alcohol can be converted into two new chiral ligands: 4,4'-bis(diphenylmethyl)-2,2'-bioxazoline and 2,2'-isopropylidenebis(4-diphenylmethyloxazoline), and further to complexes with copper(II) trifluoromethanesulfonate and nickel(II) perchlorate hexahydrate. The nickel(II) aqua complex obtained from the bisoxazoline effectively catalyzed the Diels-Alder reactions of cyclopentadiene with 3-acryloyl-2-oxazolidinone in high endo-selectivities and moderate enantioselectivities via a square planar transition structure.
- Kanemasa,Adachi,Yamamoto,Wada
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p. 681 - 687
(2007/10/03)
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- Substituted amines as tachykinin receptor antagonists
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Compounds of formula (I), and salts and prodrugs thereof, wherein Q is optionally substituted phenyl or benzhydryl; X and Y are each H or together form a group=O; Z is O, S or NR 9, where R 9 is H or C 1-6 alkyl; R 1 represents H or C 1-6 alkyl; R 2 repre
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- 2/3-(heterocyclic alkyl amino)-1-(subst.-phenyl-methoxy)-ethanes/propanes as tachykinin-receptor antagonists
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Compounds of formula (I), and salts and prodrugs thereof, wherein Q represents phenyl or benzhydryl; X and Y each represent H or X and Y together form a group =0; Z is O, S or NR 8 (R 8 is H or C 1-6 alkyl); R 1 is H, optionally substituted C 1-6 alkyl, p
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- A Synthesis of Protected Aminoalkyl Epoxides from α-Amino Acids
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The synthesis of alkylamino epoxides C is presented.Key steps include the synthesis of amino aldehyde 5 by reduction (DIBAH) of ester 3 or by oxidation of N-protected amino alcohol 4, both edducts of which are derived from amino acids.A study of the olefination of aldehyde 5 with unstabilized ylides is presented, and protected allylic amino 6, obtained in good to excellent optical purity, is oxidized (MCPBA) to epoxide C.Threo selectivity is observed in the epoxidation reaction.
- Luly, Jay R.,Dellaria, Joseph F.,Plattner, Jacob J.,Soderquist, Jeffrey L.,Yi, Nwe
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p. 1487 - 1492
(2007/10/02)
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