Answer
ˈɔto ˈvalax is the German pronunciation of Otto Wallach's name. The stress is on the first syllable of both his first and last names. The "o" in "Otto" is pronounced like the "o" in "hot," and the "a" in "Wallach" is pronounced like the "a" in "father." The "ch" at the end of "Wallach" is pronounced like the "ch" in "Bach."