The Betti reaction is a straightforward three components condensation of 2-naphthol, an aryl aldehyde and an amine, that yield easily an aminobenzylnaphthol [1]. In previous work, we investigated the intermolecular interactions in the crystal structures of chiral aminobenzylnaphthols synthesized with this procedure [2]. The crystal packings of some cyclic phosphorus derivatives of these intermediates were also investigated [3]. The most peculiar interactions that we observed in all these molecules were many short distance CH···? interactions [2]. Moreover, we observed that the use of different p-halobenzaldehydes (X = F, Cl, Br) in the Betti reaction yielded almost isostructural aminobenzylnaphthols [2]. Now, we wish to report our investigation on the crystal packings of newly synthesized aminobenzylnaphthols deriving from a Betti reaction of 2-naphthol, aryl aldehydes and valine methyl ester (Scheme 1). Significant differences with our previous work were observed mainly due to the presence of a further hydrogen bonding acceptor in the molecules (the carbonyl oxygen atom of the valine moiety). Furthermore, we observed that different para-substitutions on the starting aryl aldehyde yielded crystal structures having different packings and new intermolecular interactions.
Intermolecular Interactions In The Crystal Packings Of Structurally Related Aminoacid Derivatives Synthesized Via A Betti Reaction
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2015
Abstract
The Betti reaction is a straightforward three components condensation of 2-naphthol, an aryl aldehyde and an amine, that yield easily an aminobenzylnaphthol [1]. In previous work, we investigated the intermolecular interactions in the crystal structures of chiral aminobenzylnaphthols synthesized with this procedure [2]. The crystal packings of some cyclic phosphorus derivatives of these intermediates were also investigated [3]. The most peculiar interactions that we observed in all these molecules were many short distance CH···? interactions [2]. Moreover, we observed that the use of different p-halobenzaldehydes (X = F, Cl, Br) in the Betti reaction yielded almost isostructural aminobenzylnaphthols [2]. Now, we wish to report our investigation on the crystal packings of newly synthesized aminobenzylnaphthols deriving from a Betti reaction of 2-naphthol, aryl aldehydes and valine methyl ester (Scheme 1). Significant differences with our previous work were observed mainly due to the presence of a further hydrogen bonding acceptor in the molecules (the carbonyl oxygen atom of the valine moiety). Furthermore, we observed that different para-substitutions on the starting aryl aldehyde yielded crystal structures having different packings and new intermolecular interactions.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.