Synthesis of Organolithium Compounds of Some Group IV and V Elements

Abstract

ORGANOLITHIUM COMPOUNDS OF GROUP IV AND V ELEMENTS 619 119 g. (5.2 moles) of sodium dispersed in 5 1. of refined tetrahydrofuran. The reaction temperature was maintained at 0 to 5°d uring the addition and for 1 hr. thereafter. After further stirring at room temperature for 7 hr., the solution was cooled to 0°and 2.5 moles of freshly prepared iron(II) chloride14 in 2 1. of refined tetrahydrofuran was added in portions with vigorous stirring. The temperature rose to 18°d uring this addition. The resulting suspension was stirred at ambient temperature for 1 hr., then at 55 to 60°f or 12 hr. The solvent was then distilled at reduced pressure, and 5 1. of low boiling petroleum ether was added. The resulting solids were removed by centrifugation, and the petroleum ether and residual tetrahydrofuran were distilled to a flask temperature of 100°/10 mm. The residual concentrate was refined on a DPI molecular still to yield 1684 g.(1.34 moles, 53.5%) of an oil, vapor temperature 290- (14) Prepared by the method of G. Wilkinson, Org. Syntheses, 36, 31 (1956), using a 40 mole per cent excess of iron powder. 295°/0.004 mm. Fourteen separate fractions were collected nsD°1 .4916 to 1.4931; the spectra of all 14 fractions were practically identical. Composite, re°D°1 .4922.An infrared spectrum of this material indicated that it was free of Si-H and Si-0-Si bonds. There were weak bonds at 9 and 9.95 µ. These bonds also appeared in the spectrum of chlorotri-n-dodecylsilane.

Development of novel and efficient synthesis of group 14 element (Ge and Sn) catenates by use of samarium (II) diiodide

“…Digermanes are generally synthesized by treatment of halogermanes with an alkali metal [11]. However, the germanium-germanium bond formed by reductive coupling is easily cleaved under reductive conditions.…”

“…Organotrigermanes are mostly prepared by two methods: (1) the reaction of dihalogermanes and two equiv of halogermanes with alkali metals, and (2) by treatment of halogermanes and monohalodigermanes with alkali metals [11]. These procedures are multiplestep reactions and the corresponding trigermanes were produced in low yields.…”

A novel phenyl–bromine ligand exchange reaction on germanium by boron tribromide

“…However, it was always possible to isolate the desired monobromogermanes in pure form by extensive use of gel-permeation chromatography (GPC). Thus, benzylbromodiphenylgermane (9), bromodibenzylphenylgermane (10) and tribenzylbromogermane (11) were obtained from 6, 7 and 8 respectively (Scheme 1). The yields of the bromogermanes are listed in Table 1.…”

Synthesis of Aminophosphines and Their Applications in Catalysis

“…In the initial experiments, complex 95 reacted with a solution of LiPPh 2 in THF purchased from Sigma-Aldrich. Reactions of the dimeric cyclopalladated complex 95 in THF with LiPPh 2 synthe- sized in our lab from either PPh 3 [72][73][74], or ClPPh 2 [75][76][77] or HPPh 2 [78,79] led to the formation of either μ-Cl-μ-PPh 2 complex 97 using 1 equiv. No traces of the desired aminophosphine 90 were formed.…”