Ferrocenylethynyltin Compounds – Characterization and Reactivity towards Triethylborane

Abstract

Keywords: Alkynes / Boranes / Ferrocenes / NMR spectroscopy / Tin Ferrocenylethynyl(trimethyl)tin (1), bis(ferrocenylethynyl)dimethyltin (2), tetrakis(ferrocenylethynyl)tin (3), and chloro-(ferrocenylethynyl)dimethyltin (4) Sn NMR spectra were measured for 2 and 3, and the molecular structure of one of the modifications of 2 was determined by X-ray analysis. The reactivity of 1-4 towards triethylborane has been explored. 1,1-Organoboration takes place in all cases, and the reactions are stereoselective for 1 and 4 to give the alkenes 5 and 6, respectively, in which the stannyl and the boryl groups are in cis-positions at the C=C bond. In the case of 2, the final

Reactions of 3‐(Diethylboryl)stannoles with Isocyanates

“…According to other alkyn-1-yl group 14 compounds, [15] the CϵC bonds (114.0 and 115.4 pm) appear to be rather short. The bond angle C11-Sn-C5 …”

Selective Synthesis of Stannoles by 1,1‐Carboboration of Bis(trimethylsilylethynyl)tin Compounds Using Weakly and Strongly Electrophilic Triorganoboranes: Characterization of a Zwitterionic Intermediate

“…In the case of 3a, the molecular structure was established by X-ray crystallography ( Figure 2). Few structural data are available for dialkynyl(diorgano)-tin compounds, [12,13] and 3a is the first example with trimethylsilylethynyl groups. All the bond lengths are in the usual range, but the bond angles at tin are of interest because in 3a, as a consequence of the six-membered ring, the endocyclic bond angle C5-Sn-C9 is fairly small [100.97 (8) [a] for the bis(trimethylsilylethynyl)diorganotin compounds.…”

A novel 4‐methylene‐3‐borahomoadamantane: 1,1‐organoboration of an alkyn‐1‐ylsilane using 1‐boraadamantane

“…23,24 This is extremely helpful for assignment purposes. The assignment of the 13 C NMR signals is further supported by the typically broad NMR signals for boron-bonded 13 C nuclei. 25 The observation of 29 Si satellites corresponding to 3 J( 29 Si, 13 C) for the methylene carbon atom C(3) linked to the C C bond aids the assignment of the 1 H NMR spectra using the information from relevant two-dimensional 13 C/ 1 H HETCOR (Fig.…”

“…The proposed structure of the triene 3 in solution follows conclusively from the consistent set of NMR data ( 1 H, 11 B, 13 C, 29 Si NMR) as given in the Experimental section. The molecule 3 is chiral both in the solid state and in solution.…”

“…It is also shown in Fig. 2 that the 13 C NMR spectra were recorded with a sufficient signal-to-noise ratio for observing 29 Si satellite signals corresponding to the coupling constants J( 29 Si, 13 C). 23,24 This is extremely helpful for assignment purposes.…”