S. de la Moya Cerero

A new procedure for formylation of less active aromatics

The formylation of aromatic compounds with trifluoromethanesulphonic anhydride/dimethylformamide complex 2 takes place easily as compared to the normal Vilsmeier–Haack reaction.

Synthesis of substituted 1-norbornylamines with antiviral activity.

The reaction of (+/-)-camphor (7) with triflic anhydride (Tf2O) yields the bridgehead triflate 8. The Nametkin rearrangement of 8 to 3 was realized by treatment with triflic acid (TfOH). The solvolysis of the bridgehead triflates 3 and 8 in acetonitrile affords the N-acetyl-1-norbornylamines 4 and 9. The Pd(0)-catalyzed hydrogenation of 4 and 9 gives the amides 5 and 10. The corresponding 1-norbornylamines 2 and 13 and the N-ethyl derivatives 1, 6, 11, and 12 were obtained by basic hydrolysis or reduction with LiAlH4, respectively, of the amides 4, 5, 9, and 10. The antiviral activity of the hydrochlorides of some of the obtained 1-norbornylamines was evaluated against influenza A, herpes simplex 2, and African swine fever virus. Particularly noticeable is the activity of the hydrochlorides of 1 and 11 against influenza A virus (SI (selectivity index) = 1000).

A facile synthesis of new homochiral β-amino alcohols with norbornane framework

Abstract New homochiral 1,2-amino hydroxy derivatives of norbornane are easily prepared starting from naturally occurring 2-norbornanones.

Synthesis of homochiral 3-substituted cyclopentanones from 2-norbornanones

Abstract The cleavage of the C 1 -C 2 bond in norbornane derivatives is accomplished by base-promoted hydrolysis of α-nitroketones, periodate oxidation or Beckmann fragmentation of suitable precursors prepared from the 2-norbornanones 1 . These reactions are the basis for the synthesis of the 3-substituted homochiral cyclopentanones 6 , 10 or 15 .

Synthesis of homochiral 1,2-diols from (−)-fenchone and (+)-camphor

Abstract (+)-(1 R ,2 S )-1,2-dihydroxy-7,7-dimethylnorbornane ( 3 ) and (−)-(1 R ,2 R )-1,2-dihydroxy-3,3-dimethylnorbornane ( 12 ) have been obtained from (−)-fenchone and (+)-camphor.

Synthesis of homochiral cyclopentane derivatives by Beckmann fragmentation of 1-substituted 2-norbornanones

Abstract The fragmentation of 2-norbornanone oximes 2 was achieved by reaction with Tf2O/pyridine under mild reaction conditions, yielding homochiral (or racemic) cyclopentane derivativel.

Enantiospecific synthesis of substituted bicyclo[2.1.1]hexane-1-carboxylic acids and esters

Abstract The base promoted ring contraction of the readily accessible homochiral 2-oxo-1-norbornyl inflates 3 in 60% ethanol takes place with formation of bicyclo[2.1.1]hexane ( 4a ), ( + )- or (−)-7,7-dimethyl-bicyclo[2.1.1]hexan-1-carboxylic acids ( 4c or 4b ) and the corresponding ethyl esters in good yields.

A facile synthesis of homochiral 1-norbornanecarboxylic acids and 1-norbornanecarbonitriles

Abstract A general method for the preparation of the title compounds from naturally occurring homochiral 2-norbornanones is presented. The key step is the Tf 2 O induced Wagner-Meerwein rearrangement of the corresponding cyanohydrins.

Synthesis of methyl (1R,2S)-α,α-dimethyl-3-oxo-2-pentylcyclopentaneacetate. A model procedure for the preparation of chiral jasmonoids and prostaglandins

Abstract An expeditious procedure for the enantiospecific preparation of the trans -2,3-disubstituted cyclopentanone moiety starting from natural 2-norbornanones is described. New reaction conditions for the reaction of sterically hindered ketones with triflic anhydride, as well as for the SO cleavage of bridgehead triflates have been developed.