Group-IIIB halogens

Formation of the Group-IIIB-Group-IIIB Element Bond 6.2.5. from Gallium in Halogen Acid Media... 

This reaction is a principal method of forming IIIB-transition-metal cr bonds. The formation of thermodynamically favored alkali-metal halides or related salts and acids HX enhances the easy formation of those bonds. A second possible interaction between anionic metal bases and group-IIIB halides is a simple acid-base relationship without elimination of halide anions. However examples of this are rare, and they have been described often for group-IIIB compounds without halogen ligands ( 6.5.3.2). 

Gagliardi, E. and Brodar, B., Thin-layer chromatography of metals on cellulose. Behavior of Group IIIB in the halogenic acid-alcohol system, Chromatographia, 2, 267, 1969. 

Reactions at a Group IIIB Element Center 10.2.4.1. Reactions of Halogens and Hydrogen Halacids... 

The introduction of an a-chlorine as a second activating group into jS-chloro-a-phenylsulphonylethylene has only small effect on the reactivity. With MeO- ion the rate increases 2-3- to 3-8-fold, and with PhS- ion 4- to 21-fold. The relative activating ability of the halogens was discussed in Section (IIIB,3). 

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