Molecular and crystal structure of N-(fluorodimethylsilylmethyl)pyrrolidone-2

Synthesis and Structure ofN-(Silylalkyl)amides: Rhodium-Catalyzed Hydrosilylation of Enamides

“…The hydrogen atom in 2f and 2k is rather close to the oxygen atom. This is in marked contrast to the case of the N -(silylmethyl)amides having the electron-withdrawing groups such as fluorine and chlorine on the silyl atom . It is probably because the energy level of the σ* orbital of the silicon−carbon bond is not low enough to interact with the lone-pair electrons on the carbonyl group, and the steric factor may be a dominant factor to control the conformations.…”

“…N -(Silylalkyl)amides: X-ray Molecular Structure Analysis and Hydrolysis. The structures of N -(silylalkyl)amides are of great interest, in particular, whether there is an interaction between the silyl group and the oxygen atom of the carbonyl group or not . After several disappointing results, the single crystal of 2f and N -(1-dimethylphenylsilyl)propylacetamide 2k 5 was successfully obtained.…”

Sulfur-Induced Pentacoordination in Cyclic Silanes1

“…(b) Part 105: T. K. Prakasha Recently, we have found that sulfur also serves as a donor atom with acyclic (J) 29 and cyclic (K-M) 29,30 oxysilanes in promoting increased coordination toward a trigonal bipyramidal geometry. However, a more narrow range of Si-S ax distances (2.98-3.29 Å) is evident in these derivatives compared to that found for silanes with nitrogen 17-20 and oxygen [23][24][25][26][27][28] acting as donor atoms, i.e., 0.31 Å. Again these Si-S distances are between the covalent 21 and van der Waals 22 sum of 2.20 and 3.90 Å, respectively.…”

“…A sampling of the types of silanes studied by X-ray diffraction that incorporate nitrogen donation [17][18][19][20] in Table 1 shows Si-N ax distances ranging from 1.97 to 2.66 Å, well within the limits of a Si-N single bond value (1.93 Å 21 ) and a van der Waals distance (3.65 Å 22 ). Similarly, Table 2 illustrates structural data on a sampling of silanes that have undergone oxygen atom coordination [23][24][25][26][27][28] providing Si-O ax lengths from 1.75 to 2.40 Å, over a similar range of values as exhibited with silanes having nitrogen atom coordination, 0.65 Å for the oxygen series X Abstract published in AdVance ACS Abstracts, May 1, 1996.…”

Synthesis, X-ray Structure, and Electronic Properties of Oligosilanes Containing Pentacoordinate Silicon Moieties at Internal Positions

“…Strong coordination in these molecules is also supported by the IR spectra (in KBr) which exhibited the ν(CO) bands at 1603 cm -1 for 3 and 1607 cm -1 for 4 . The ν(CO) of analogous ( 5 ) also appeared at the same region (1598 cm -1 ),7a indicating that replacement of two equatorial methyl groups in 5 by two silyl groups has no influence on the strength of the O−Si bond . This result is somewhat surprising, because the presence of an electropositive ligand such as silicon in the equatorial position is supposed to weaken the coordination bond. ,7c …”