Moses Gomberg was trying to synthesize a carbon compound called hexaphenylethane when he inadvertently synthesized triphenylmethyl (trityl for short), a mysterious, highly reactive, unstable substance. He recognized that he had found the long-elusive free radical and showed that carbon is not always tetravalent — the then prevailing view.

Gomberg published his findings in 1900, but the existence of triphenylmethyl and other organic free radicals remained in dispute for nearly a decade. They were viewed as a curiosity even after the scientific community recognized their existence. Not until the 1930s did free radicals enter the mainstream of organic chemistry.