Diastereo- and Enantioselective Synthesis of trans-2-Amino-Cycloalkane-1-Carboxylic Acids via Intramolecular Tandem Michael-Addition/α-Alkylation Using TMS-SAMP as Chiral Equivalent of Ammonia

Abstract

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Enantioselective Synthesis of ?-amino acids: A Review

“…Each approach has itsown advantages and limitations while more than 80 numbers of different approaches have been discussed here but the organo-Rh based and heterogeneous catalyzed approach is found to be more effective ( Scheme 1,2,4,11,12,13,28,29) and (Scheme 8,9,33,34,35,36,37,45,54,63). Other approaches can also be considered to synthesize enantioselective amino acids ( Scheme 11,13,15,40,45,50,61,62,68,70,74). No doubt, the growing interest in enantioselective β-amino acids will stimulate new and improved methods for their synthesis in near future.…”

“…TMS-SAMP as anucleophile was used by Enders et al to synthesis N-silylated β-hydrazino-estersin as aza analogous Michael addition process [67]. In a Tandem aza Michael addition intramolecular cyclization, the same reaction sequence was also applied to the synthesis of cyclic β-amino acids and heterocyclic β-amino acids [68]. Sibi et al reported β-amino acid derivatives with 97% yield (Scheme 45) [69].…”

“…This resolved Enders et al synthesised cycloheptane based β-amino acids using a conjugate addition/alkylation reaction of α,β-unsaturated ester (Scheme 62). This gave the cyclic chiral intermediate in >96% yield was cleaved to β-amino acid [67,68].…”

Opioid Deltorphin C Analogues Containing cis- or trans-2- or 3- or 4-Aminocyclohexanecarboxylic Acid Residues

“…Therefore, we designed and synthesized a series of conformationally restricted deltorphin C (Del-C) analogues (Scheme 1) containing cis-and trans-2-or 3-or 4-ACCA at position 2 and evaluated their binding affinity for-µ-, 6-and K-receptors and their resistante to degradation by plasma or brain enzymes. Peptidomimetic 2-or 3-aminocycloalkane-1-carboxylic acid have been designed to replace a single residue in bioactive peptides [18][19][20][21][22] or to prepare oligomers with specific secondary structural preferences (foldamers) [23]. Amino acid derivatives and solid support were purchased from Novabiochem AG (Laufelfingen, Switzerland).…”

Synthesis of Alicyclictrans-β-Amino Acids fromcis-β-Hydroxycycloalkane­carboxylates

“…5 The Michael initiated ring closure (MIRC) reaction has been successfully used for the preparation of (1S,2S)-2-aminocycloheptanecarboxylic acid with (S)-(-)-1-(trimethylsilylamino)-2-(methoxymethyl)pyrrolidine (SAMP) as chiral ammonia equivalent. 6,7 The cis-derivatives of the eight-membered b-amino acids have been obtained from cyclooctadiene via its b-lactam 8 or by reduction of 2-acetylamino-1-cyclooctenecarboxylate, 9 but the trans-counterpart has not been successfully synthesized so far.…”