The addition of hydrogermanes across multiple carboncarbon bonds typically relies on the activation of the Ge-H bond by transition metal complexes (mainly Pd, Ru, Rh, and Pt) or radical initiators such as Et3B/O2 and AIBN. Recently, a new generation of catalysts based on earth-abundant first-row transition metal carbonyl complexes of Fe, Mn 4 , and Co 5 have also attracted considerable attention. Moreover, hydrogermylation of alkynes as well as transfer hydrogermylation of alkenes have been successfully achieved using transition metal-free, boron-containing catalyst: B(C6F5)3. However, to the best of our knowledge there is no report on the use of commercially available alkali metal trialkylborohydrides in this process. The position of germanium between silicon and tin in group 14 of the periodic table causes organogermanium compounds to exhibit properties similar to those of organosilicon and organotin compounds, however, the synthetic chemistry of this element is still in its infancy, and therefore, organogermanes have not received significant attention. On the other hand, organogermanes have found use as essential cross-coupling partners in selective carbon-carbon bond formation reactions to circumvent the limitations of traditional organometallic reagents. Recent progress in the application of organogermanes has been outlined in the work of Schoenebeck and Fricke, who have shown that organogermanium compounds possess unique and complementary reactivity in relation to that of other organometallic coupling agents, paving the way for their further interesting applications in organic synthesis. We have already reported that NaHBEt3 can be used as a catalyst for Markovnikov selective hydrosilylation of aromatic alkenes and dehydrogenative silylation of terminal alkynes. NaHBEt3 has also been demonstrated by Thomas and coworkers to catalyze hydroboration of phenylacetylene with pinacolborane to give (E)-styryl boronic ester. Given the growing interest in application of organogermanes in organic synthesis and the mechanistic similarity of the hydrosilylation and hydroboration to already known occurrences of hydrogermylation, we decided to study the reactivity of alkali metal triethylborohydrides in the presence of aromatic alkenes and primary and secondary germanes to examine the impact of these commonly used reductants on the course of the hydrogermylation process. Driven by previous successful experiments in hydrosilylation, we initialized the research on hydrogermylation by screening the catalytic activity of different trialkylborohydrides in a reaction of diphenylgermane with styrene. Also as previously, toluene has been used as a solvent and reactions were carried out for 20 hours at 100 °C. The first experiments unfolded unexpectedly, producing diphenyl (2phenylethyl) germane exclusively, a product of opposite regioselectivity compared to hydrosilylation (Scheme 2). Scheme 2. Opposite selectivity of hydrosilylation and hydrogermylation under the same conditions.