Über die Stereochemie der Hexahydro‐toluidine

Abstract

1'1 P. S a b a t i e r uiitl .I. E. S e n d e r e n s , C. r. 138, 1258 (C. t904. II 105); 2) S . N a m r t k i n , C. 1910, I1 1377.

The Action of Nitrous Acid on some Alicyclic Amines

“…4-cyclohexylcyclohexylamine, and 4-iert-butylcyclohexylamine were prepared by the reduction of the corresponding cyclohexanone oximes with sodium and alcohol. It is generally agreed that monosubstituted cyciohexylamines prepared in this manner have the trans configuration (2), although the reduction of 3-methylcyclohexanone oxime is reported to yield both cis-and írans-3-methylcyclohexylamine (3).…”

Practical Isolation of the (1R,2R)-Enantiomer from a Racemic cis/trans Mixture of 2-Methyl-1-cyclohexanamine

“…NMR spectra were recorded on a Bruker BioSpin machine. 1 H shifts were referenced to DMSO-d 6 at 2.49 ppm and CDCl 3 at 7.26 ppm. 13 C shifts were referenced to DMSO-d 6 at 39.52 ppm.…”

“…GC analysis of the Mosher-amides revealed an ee of 97.9%. 1 (1R,2R)-2-Methyl-1-cyclohexanamine hydrochloride ((−)-(1R,2R)-1-HCl). Crop-6 (72 g, 156 mmol) was suspended in TBME (500 mL) and ice water (500 mL).…”

“…ee = 98.3% (tosylamide method). 1 The Supporting Information is available free of charge on the ACS Publications website at DOI: 10.1021/acs.oprd.7b00263.…”

“…The hydrogenation of N -(2-tolyl)­acetamide ( 2 ) or anthranilic acid ( 3 ) gave direct access to racemic trans -substituted cyclohexane cores that were further transformed to 1 . , Hydroboration of 1-methylcyclohex-1-ene ( 4 ) was accomplished nonstereoselectively , or stereoselectively , and resulted after amination of the carbon-boron bond in the formation of 1 ; in the latter case, (1 S ,2 S )- 1 HCl was obtained with 99% enantiomeric excess (ee) following a five-step sequence in 48% overall yield. Aziridination of cyclohexene ( 5 ) and subsequent ring opening led to (1 R ,2 R )- 1 in four more steps .…”