Chaim Weizmann Zionist activity, and executed in 1939. His fate became known to his wife and children only in 1955. Maria Weizmann was a doctor who was arrested as part of Stalin's fabricated "Doctors' plot" in 1952 and was sentenced to five years' imprisonment in Siberia. She was released following Stalin's death in 1953, and was permitted to emigrate to Israel along with her husband in 1956. Weizmann was married to Vera Khatzmann. The couple had two sons. The younger one, Flight Lieutenant Michael Oser Weizmann (1916–1942), fought in the Royal Air Force during World War II. While serving as a pilot
Chaim Weizmann of Mandate Palestine. In 1942, Weizmann was invited by President Franklin D. Roosevelt to work on the problem of synthetic rubber. Weizmann proposed to produce butyl alcohol from maize, then convert it to butylene and further to butadiene, which is a basis for rubber. According to his memoirs, these proposals were barred by the oil companies. In 1939, a conference was established at St James's Palace when the government drew up the May 1939 White Paper which severely curtailed any spending in the Jewish Home Land. Yishuv was put back to the lowest priority. At the outbreak of war the