3- Pentanone crystal structure

Fig. 7.3. Crystal structures of some lithium etiolates of ketones. (A) Unsolvated hexameric enolate of methyl t-butyl ketone (B) tetrahydrofuran solvate of tetramer of enolate of methyl r-butyl ketone (C) tetrahydrofuran solvate of tetramer of enolate of cyclopentanone (D) dimeric enolate of 3,3-dimethyl-4-(r-butyldimethylsiloxy)-2-pentanone. (Structural diagrams are reproduced from Refs. 66-69.) by permission of the American Chemical Society and Verlag Helvetica Chimica Acta AG.

A crystal structure is available for the SnCl4 complex of 2-benzyloxy-3-pentanone.89 The steric shielding by the methyl group with respect to the C=0 is evident in this structure (Figure 2.1). NMR studies indicate that the reaction involves... 

The single crystal X-ray structure of fra s-methyliodo difluoro[3,3 -(trimethylenedinitrolo)bis(2-pentanone oximato)]borate rhodium(III) (62) shows that the Rh sits in the plane established by the four N atoms, with the I and the Me in the axial positions (2.813 A and 2.090 A, respectively). The two six-membered rings resemble a chair conformation, with the BF2 bridge bent toward the axial methyl group, and the propylene bent toward the iodine atom.896... 

---