1260229-35-3Relevant academic research and scientific papers
The Doubly Base-Stabilized Diborane(4) [HB(I-hpp)]2 (hpp = 1,3,4,6,7,8-hexahydro-2H-pyrimido[1,2-a]pyrimidinate): Synthesis by Catalytic Dehydrogenation and Reactions with S8 and Disulfides
Schulenberg, Nikola,Ciobanu, Oxana,Kaifer, Elisabeth,Wadepohl, Hubert,Himmel, Hans-Joerg
, p. 5201 - 5210 (2011/02/24)
In this work we report on new experiments on the catalytic dehydrogenation of [H2B(I-hpp)]2 leading to the doubly base-stabilized diborane(4) [HB(I-hpp)]2 featuring two hpp bridges (hpp = 1,3,4,6,7,8-hexahydro-2H-pyrimido[1,2-a]pyrimidinate) under mild conditions. Several dehydrogenation (pre)catalysts were tested. The best one turned out to be Ru3(CO)12, allowing quantitative dehydrogenation already at 60 °C. Subsequently we subjected [HB(I-hpp)]2 to reactions with S8 and disulfides (Ph2S2 and Bn2S2, Bn = benzyl). Reaction with S8 leads to oxidative insertion of one sulfur atom into the B-B bond and formation of [HB(I-hpp)]2(I-S). In the case of disulfides, substitution reactions leading to the doubly base-stabilized diborane(4) species [RSB(I-hpp)]2 and HB(I-hpp) 2BSR (R = Ph or Bn) compete with sulfuration again leading to [HB(I-hpp)]2(I-S). Catalytic dehydrogenation of [H 2B(I-hpp)]2 leads to the doubly base-stabilized diborane(4) [HB(I-hpp)]2. Oxidative sulfuration of the B-B bond in [HB(I-hpp)]2 gives [HB(I-hpp)]2(I-S) . A mixture ofsulfuration and substitution products is formed for reactions with disulfides. Copyright
