1H n.m.r. study and conformation of 3,3-dimethyl-3-sila-1-heterocyclohexanes and derivatives (heteroatom SiCl2, SiMe2, O, NMe, S, Se, Te)

✍ Scribed by Marc J. O. Anteunis; Raymond Dedeyne

• Book ID: 102950510
• Publisher: John Wiley and Sons
• Year: 1977
• Tongue: English
• Weight: 595 KB
• Volume: 9
• Category: Article
• ISSN: 0749-1581
• DOI: 10.1002/mrc.1270090304

✦ Synopsis

Abstract

It is found that the basic form of the 3,3‐dimethyl‐3‐sila‐1‐heterocyclohexane family (heteroatom X = O, NMe, S, Se, Te, SiMe~2~, SiCl~2~) is the chair, having ring torsion angles in the aliphatic region tending to be somewhat more puckered (up to 7°) than in cyclohexane, except next to Si when the other heteroatom is relatively small. The 5‐tertiarybutyl‐, 6‐methyl‐ and 2‐phenyl derivatives are all anancomeric, except for the latter two derivatives when X = NMe. A 5‐tertiarybutyl group causes an additional deformation, e.g. an increased puckering of the aliphatic C‐4C‐5C‐6 region (buttressing effect). Other ^1^H n.m.r. features are discussed in detail, and the behaviour of the 3‐sila‐1‐heterocyclohexanes is compared with other 1,3‐diheterocyclohexanes.