arsines

https://doi.org/10.1351/goldbook.A00452
AsH3 and compounds derived from it by substituting one, two or three hydrogen atoms by hydrocarbyl groups: R3As, RAsH2, R2AsH, R3As (RH) are called primary, secondary and tertiary arsines, respectively. A specific arsine is preferably named as a substituted arsane, e.g. CH3CH2AsH2 ethylarsane.
See: arsanes
Source:
PAC, 1995, 67, 1307. 'Glossary of class names of organic compounds and reactivity intermediates based on structure (IUPAC Recommendations 1995)' on page 1319 (https://doi.org/10.1351/pac199567081307)