An efficient and practical synthesis of BINAM derivatives by diastereoselective [3,3]-rearrangement

This work describes an efficient, practical, and diastereoselective synthesis of enantiomerically pure BINAM derivatives by utilizing the acid-catalyzed [3,3]-sigmatropic rearrangement of readily accessible N-(−)-menthoxycarbonyl-diaryl hydrazines as a key step. The yield of the rearrangement is very high and two diastereomers thus obtained are easily separable.

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(1R,2S,5R)-2-Isopropyl-5-methylcyclohexyl hydrazinecarboxylateC11H22N2O2[α]D25 = −71.2 (c 1, CHCl3)Source of chirality: (–) - MentholAbsolute configuration: (1R,2S,5R)

(1R,2S,5R)-2-Isopropyl-5-methylcyclohexyl 1-(naphthalen-2-yl)hydrazine-1-carboxylateC21H28N2O2[α]D25 = −42.1 (c 1, CH2Cl2)Source of chirality: (–) - MentholAbsolute configuration: (1R,2S,5R)

(1R,2S,5R)-2-Isopropyl-5-methylcyclohexyl 1,2-di(naphthalen-2-yl)hydrazine-1-carboxylateC31H34N2O2[α]D25 = −78.9 (c 1, CH2Cl2)Source of chirality: (–) - MentholAbsolute configuration: (1R,2S,5R)

(1R,2S,5R)-2-Isopropyl-5-methylcyclohexyl 2-(6-methoxynaphthalen-2-yl)-1-(naphthalen-2-yl)hydrazine-1-carboxylateC32H36N2O3[α]D25 = −42.1 (c 0.5, CH2Cl2)Source of chirality: (–) - MentholAbsolute configuration: (1R,2S,5R)

(1R,2S,5R)-(2-Isopropyl-5-methylcyclohexyl)[(R)-2′-amino-1,1′-binaphthalen-2-yl] carbamateC31H34N2O2[α]D25 = +38.8 (c 0.5, CH2Cl2)Source of chirality: (–) - MentholAbsolute configuration: (1R,2S,5R), (R)

(1R,2S,5R)-(2-Isopropyl-5-methylcyclohexyl)[(S)-2′-amino-1,1′-binaphthalen-2-yl] carbamateC31H34N2O2[α]D25 = −58.3 (c 0.5, CH2Cl2)Source of chirality: (–) - MentholAbsolute configuration: (1R,2S,5R), (S)

(1R,2S,5R)-2-Isopropyl-5-methylcyclohexyl [(R)-2′-amino-6′-methoxy-1,1′-binaphthalen]-2-yl] carbamateC32H36N2O3[α]D25 = +26.1 (c 0.25, CH2Cl2)Source of chirality: (–) - MentholAbsolute configuration: (1R,2S,5R), (R)

(1R,2S,5R)-2-Isopropyl-5-methylcyclohexyl [(S)-2′-amino-6′-methoxy-1,1′-binaphthalen]-2-yl] carbamateC32H36N2O3[α]D25 = −28.3 (c 0.25, CH2Cl2)Source of chirality: (–) - MentholAbsolute configuration: (1R,2S,5R), (S)

(R)-[1,1′-Binaphthalene]-2,2′-diamineC20H16N2[α]D25 = +156 (c 1, pyridine)Source of chirality: (–) - MentholAbsolute configuration: (R)

(S)-[1,1′-Binaphthalene]-2,2′-diamineC20H16N2[α]D25 = −156 (c 1, pyridine)Source of chirality: (–) - MentholAbsolute configuration: (S)

(R)-6-Methoxy-[1,1′-binaphthalene]-2,2′-diamineC21H18N2O[α]D25 = +61.0 (c 0.25, CH2Cl2)Source of chirality: (–) - MentholAbsolute configuration: (R)

(S)-6-Methoxy-[1,1′-binaphthalene]-2,2′-diamineC21H18N2O[α]D25 = −61.0 (c 0.25, CH2Cl2)Source of chirality: (–) - MentholAbsolute configuration: (S)