Crystal structure of a fuse cyclohexane with an axial t-butyl group: 8β-t-butyl-trans-decahydroquinoline

✍ Scribed by Karl D. Hargrave; Ernest L. Eliel

• Publisher: Elsevier Science
• Year: 1979
• Tongue: French
• Weight: 250 KB
• Volume: 20
• Category: Article
• ISSN: 0040-4039
• DOI: 10.1016/s0040-4039(01)86244-4

✦ Synopsis

Butyl-trans-decahydroquinoline picrate crystallizes as a double chair with an axial t-butyl group. Except for a 16.2' torsion of the t-butyl group away from the staggered conformation, the molecule displays only minor conformational deformations. A t-butyl group substituted on a cyclohexane ring tends to avoid the axial position and thus serves as a "holding group" for the cyclohexane chair, preventing ring reversa1.l The first cyclohexane with a potentially axial t-butyl group -tr~ns-I ,3-di-t-butylcyclohexane was synthesized in 1960,2 but this species,3 as well as the corresponding cis-1,4-di-t-buty13'4 and cis,trans-1,3,5-tri-t-butyl 5 analogs appear to exist predominantly in the twist-boat form. A twist-boat was also originally assumed for the cis-1,2-di-t-butylcyclohexane, 6 but later work7 suggests that this compound in fact exists as a chair with one