The Structure of the 1:1 Adduct of “Hector′s Base” With Arylcyanamides Bond Switch on Hypervalent Sulfur

Abstract

The structure of the 1:1 adduct of “Hector’s base” with arylcyanamides was determined by X-ray analysis of tris-p-bromophenyl derivative (1a). The molecule is almost planar and the strong interaction was exemplified between the sulfur and the nitrogen atoms.

Studies on low‐coordinated nitrogen, phosphorus, sulfur, and selenium compounds

“…Similarly, the N-nitrosoimine of Hector's base 80 gave 81 as a main product, which exhibited an abnormally high m C‫ס‬N value (1660 cm ‫1מ‬ ), and 81 was also obtained by reaction of Hector's base with PhNHCN, which was a decomposition product of 80 [79]. The structure of 81 was confirmed, using the compound containing three p-bromophenyl groups instead of three phenyl groups, by X-ray crystallography [80]. The high m C‫ס‬N value is attributed to the short bond length (128 pm) of the side chain C‫ס‬N bond in 81a and the N • • • S bond length (253.8 pm) in 81a is shorter than the sum (335 pm) of the van der Waals radii of S and N atoms, indicating an interaction between the N and S atoms [80].…”

“…The structure of 81 was confirmed, using the compound containing three p-bromophenyl groups instead of three phenyl groups, by X-ray crystallography [80]. The high m C‫ס‬N value is attributed to the short bond length (128 pm) of the side chain C‫ס‬N bond in 81a and the N • • • S bond length (253.8 pm) in 81a is shorter than the sum (335 pm) of the van der Waals radii of S and N atoms, indicating an interaction between the N and S atoms [80]. An intermediate for the formation of 81 is considered to be a hypervalent sulfur compound 82 [80].…”

“…The high m C‫ס‬N value is attributed to the short bond length (128 pm) of the side chain C‫ס‬N bond in 81a and the N • • • S bond length (253.8 pm) in 81a is shorter than the sum (335 pm) of the van der Waals radii of S and N atoms, indicating an interaction between the N and S atoms [80]. An intermediate for the formation of 81 is considered to be a hypervalent sulfur compound 82 [80]. From comparison of the 13 C NMR data with those of related compounds, the N • • • S interaction was attributed to an electron transfer from the N atom to the S atom [81].…”

The structure of 5-(N-methylthiocarbamoylimino)-4-phenyl-3-phenyl-amino-4H-1,2,4-thiadiazoline

“…The structure consists of molecules of constitution (I), in which simple addition of methyl isothiocyanate to Hector's base (II) (Butler, Glidewell & Liles, 1978a) has occurred. This is in marked contrast to the addition of carbon disulphide to Hector's base to give (III) (Butler, Glidewell & Liles, 1978b), and of 4-bromophenylcyanamide to the 4-bromophenyl analogue of Hector's base to give (IV) (Akiba, Tsuchiya, Inamoto, Onuma, Nagashima & Nakamura, 1976).…”

Studies on hypervalent compounds and synthetic work using heteroaromatic cations

“…Compound 16 was also obtained by a reaction of Hector's base with PhNHCN, which was one of decomposition products of 14 18. The structure of 16 was confirmed by X‐ray crystallography of the compound bearing three p ‐bromophenyl groups ( 16′ ) instead of three phenyls of 16 19. The high ν C=N value is attributed to the short bond length (1.28 Å) of the side chain CN bond in 16′ and the N ⋅⋅⋅ S bond length (2.538 Å) in 16′ is considerably shorter than the sum (3.35 Å) of the van der Waals radii of S and N atoms, indicating the presence of an attractive interaction between the two atoms.…”