Abstract
A new solid amine borane is reported here. The reaction of (R)‐(−)‐1‐cyclohexylethylamine (a liquid at room temperature) with borane dimethylsulfide yields crystals of pure (R)‐N‐1‐cyclohexylethylamine borane C$_6$H$_{11}$CH(CH$_3$)NH$_2$BH$_3$(CHEAB). The successful synthesis was confirmed by molecular analyses (FTIR, Raman and NMR). The crystals are in the form of millimeter‐sized translucent sticks, which allowed determining that CHEAB crystallizes in the orthorhombic system, the space group being P2$_1$2$_1$2$_1$. All of the characterization results, together with DFT calculations, strongly suggest the occurrence of intermolecular dihydrogen bonds between antiparallel NH$_2$BH$_3$groups that are in a trimeric configuration.