ChemInform Abstract: PARTIAL ASYMMETRIC PUMMERER REACTION OF ARYL PROP-2-YNYL SULFOXIDE WITH ACETIC ANHYDRIDE

1978 ◽  
Vol 9 (13) ◽  
Author(s):  
T. NUMATA ◽  
O. ITOH ◽  
S. OAE
Keyword(s):  
Acetic Anhydride ◽  
Pummerer Reaction

Pummerer Reaction of Sulfoxides in Acetic Anhydride Catalyzed by Al-MCM-41

2016 ◽  
Vol 45 (1) ◽  
pp. 16-18 ◽  
Author(s):  
Suguru Ito ◽  
Yoshihiro Kubota ◽  
Masatoshi Asami
Keyword(s):  
Acetic Anhydride ◽  
Pummerer Reaction ◽  
Mcm 41

scholarly journals PARTIAL ASYMMETRIC PUMMERER REACTION OF ARYL PROP-2-YNYL SULFOXIDE WITH ACETIC ANHYDRIDE

1977 ◽  
Vol 6 (8) ◽  
pp. 909-912 ◽  
Author(s):  
Tatsuo Numata ◽  
Osamu Itoh ◽  
Shigeru Oae
Keyword(s):  
Acetic Anhydride ◽  
Pummerer Reaction

Stereoselective Pummerer reaction of 4-p-chlorophenylthiane S-oxide with acetic anhydride

1979 ◽  
Vol 20 (2) ◽  
pp. 161-162 ◽  
Author(s):  
Tatsuo Numata ◽  
Osamu Itoh ◽  
Shigeru Oae
Keyword(s):  
Acetic Anhydride ◽  
Pummerer Reaction

ChemInform Abstract: Pummerer Reaction of Sulfoxides in Acetic Anhydride Catalyzed by Al-MCM-41.

ChemInform ◽  
2016 ◽  
Vol 47 (28) ◽  
Author(s):  
Suguru Ito ◽  
Yoshihiro Kubota ◽  
Masatoshi Asami
Keyword(s):  
Acetic Anhydride ◽  
Pummerer Reaction ◽  
Mcm 41

Cyclization of cysteinylglycine sulfoxides under Pummerer reaction conditions

1979 ◽  
Vol 57 (18) ◽  
pp. 2412-2425 ◽  
Author(s):  
Saul Wolfe ◽  
Peter Michael Kazmaier ◽  
Hillar Auksi
Keyword(s):  
Acetic Anhydride ◽  
Trifluoroacetic Acid ◽  
Carboxyl Group ◽  
Reaction Conditions ◽  
Pummerer Reaction ◽  
Peptide Cyclization

A number of sulfoxides derived from 3-benzylthiopropionic acid, S-benzylcysteine, and S-phenylcystelne have been synthesized and exposed to typical Pummerer reaction conditions. Cyclization of the S-benzyl sulfoxides to six-membered or seven-membered heterocyclic rings (1,3-thiazin-4-ones and 1,3,6-oxathiazepines) is observed only in acetic anhydride solvent and only after conversion of the carboxyl group to an amide or peptide. Cyclization of S-phenylcysteinyl amides to β-lactams could not be achieved. The thiazolidine isomers of the six- and seven-membered rings have been synthesized and found not to be intermediates in the acetic anhydride reactions. The thiazolidines do rearrange to the six- and (or) seven-membered rings in anhydrous trifluoroacetic acid solvent. S-Benzylphthalimidocysteinylglycine sulfoxide, a 3:2 mixture of epimers at sulfur, affords a 3:2 mixture of isomeric thiazinones. A mechanism for these cyclizations is proposed, and it is suggested that the configuration at sulfur controls the configuration at the new asymmetric centre in the product.

On the relationships between 18O-transfer, diastereotopic selectivity, and asymmetric induction in an intramolecular Pummerer reaction

1979 ◽  
Vol 57 (18) ◽  
pp. 2404-2411 ◽  
Author(s):  
Saul Wolfe ◽  
Peter Michael Kazmaier ◽  
Hillar Auksi
Keyword(s):  
Acetic Anhydride ◽  
Opposite Sign ◽  
Optically Active ◽  
Asymmetric Induction ◽  
Carboxyl Group ◽  
Initial Attack ◽  
Deuterium Labelling ◽  
Pummerer Reaction ◽  
Reaction Proceeds ◽  
The Relationship

The cyclization of benzyl 2-carboxyphenyl sulfoxide (1) to 2-benzylbenzoxathiane-6-one (2) has been examined by a combination of 18O-labelling of the sulfoxide oxygen, stereoselective deuterium labelling in the benzylic position, and the use of optically active compounds. With dicyclohexylcarbodiimide (DCC) as the cyclizing agent, the reaction proceeds with 55.8% retention of the sulfoxide oxygen, 57.8% preference for abstraction of one of the diastereotopic methylene protons, and it produces a 61.4/38.6 mixture of enantiomers. It is proposed that all three experimental observables are controlled by the competition between initial attack of the DCC upon the sulfoxide oxygen and upon the carboxyl group, and a mechanism is proposed for the reaction which clarifies the relationship between these observables. In agreement with earlier work by Stridsberg and Allenmark, DCC affords 2 having the opposite sign of rotation from 1, and acetic anhydride affords 2 having the same sign of rotation as 1. Asymmetric induction in the latter reaction is significantly less than with DCC because of competing epimerization at sulfur, but the origin of the differences in the sign of rotation of 2 under the different conditions has been clarified by the finding that there is less than 40% retention of the sulfoxide oxygen with acetic anhydride as the reagent.

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