The high-temperature syntheses of the low-valent halogenides P₂I₄, Te₂Br, α-Te₄I₄, Te₄(Al₂Cl₇)₂, Te₄(Bi₆Cl₂₀), Te₈(Bi₄Cl₁₄),Bi₈(AlCl₄)₂, Bi₆C_l7,and Bi₆Br₇, as well as of WSCl₄ andWOCl₄ have been replaced by resource-efficient low-temperature syntheses in room temperature ionic liquids (RTILs). The simple one-pot syntheses generally do not require elaborate equipment such as twozone furnaces or evacuated silica ampoules. Compared to the published conventional approaches, reduction of reaction time (up to 80%) and temperature (up to 500 K) and, simultaneously, an increase in yield were achieved. In the majority of cases, the solid products were phase-pure. X-Ray diffraction on single crystals (redetermination of 11 crystal structures) has demonstrated that the quality of the crystals from RTILs is comparable to that of products obtained by chemical transport reactions.