Synthesis, Formation Mechanism, and Structure of K[BH 3 S(CH 3 )BH 3 ] and Its Application in Preparation of KB 3 H 8 .

The design, synthesis, and applications of new boranes are eternal topics in boron chemistry. A new bis(borane)alkanethiolate salt, K[BH 3 S(CH 3 )BH 3 ], was synthesized in high yield by the reaction of K with (CH 3 ) 2 S·BH 3 at room temperature. The formation mechanism was elucidated based on experimental and theoretical studies. The single-crystal structure of the K[BH 3 S(CH 3 )BH 3 ]·18-crown-6 adduct was determined in which the B-S-B bonding information of K[BH 3 S(CH 3 )BH 3 ] was illustrated for the first time. Using K[BH 3 S(CH 3 )BH 3 ] as a starting material, KB 3 H 8 was successfully synthesized.