In 1941 he graduated from the musical and pedagogical department of the Sverdlovsk Music College (lecturers were A.A. Lyudmilin, M.A. Mebel, E.A Holstein), in 1950 he ended the conductor-choral faculty of the Ural Conservatory (the class of Professor M.I Paverman, Professor A.V Preobrazhensky).
In 1950-1951 Leonard was a choirmaster at the Sverdlovsk Opera and Ballet Theater. In 1951-1955 he was a choirmaster and assistant of chief conductor at the Perm Opera and Ballet Theater. In 1955-1957 Leonard was the chief choirmaster at the Sverdlovsk Opera and Ballet Theater.
In 1957-1960 he was an advisor on the of musical theater art in Ulan Bator, Mongolian People's Republic. In 1960-1991 Leonard worked as the main choirmaster at the Voronezh Opera and Ballet Theater. In 1962-1968 he was the founder and artistic director of the Academic Choir at the Voronezh State University, and also of the opera studio at the House of Culture named after the 50th anniversary of October, where he staged the following theatrical performances: "Zaporozhets beyond the Danube" by Semen Gulak-Artemovsky, "Wedding in Malinovka" by Boris Alexandrov.