Elias James Corey (born July 12, 1928) is an American organic chemist. In 1990, he won the Nobel Prize in Chemistry "for his development of the theory and methodology of organic synthesis", specifically retrosynthetic analysis. Regarded by many as one of the greatest living chemists, he has developed numerous synthetic reagents, methodologies and total syntheses and has advanced the science of organic synthesis considerably.
Biography
E.J. Corey (the surname was anglicized from Levantine Arabic Khoury, meaning priest) was born to Lebanese Greek Orthodox Christian immigrants Fatima (née Hasham) and Elias Corey in Methuen, Massachusetts, north of Boston. His mother changed his name from William to "Elias" to honor his father, who died eighteen months after Corey's birth. His widowed mother, brother, two sisters, aunt and uncle all lived together in a spacious house, struggling through the Great Depression. As a young boy, Corey was independent and enjoyed sports such as baseball, football, and hiking. He attended a Catholic elementary school and Lawrence High School in Lawrence, Massachusetts.
At the age of 16 Corey entered MIT, where he earned both a bachelor's degree in 1948 and a Ph.D. under Professor John C. Sheehan in 1951. Upon entering MIT, Corey's only experience with science was in mathematics, and he began his college career pursuing a degree in engineering. After his first chemistry class in his sophomore year he began rethinking his long-term career plans and graduated with a bachelor's degree in chemistry. Immediately thereafter, at the invitation of Professor John C. Sheehan, Corey remained at MIT for his Ph.D. After his graduate career he was offered an appointment at the University of Illinois at Urbana–Champaign, where he became a full professor of chemistry in 1956 at the age of 27. He was initiated as a member of the Zeta chapter of Alpha Chi Sigma at the University of Illinois in 1952. In 1959, he moved to Harvard University, where he is currently an emeritus professor of organic chemistry with an active Corey Group research program. He chose to work in organic chemistry because of "its intrinsic beauty and its great relevance to human health". He has also been an advisor to Pfizer for more than 50 years.
Among numerous honors, Corey was awarded the National Medal of Science in 1988, the Nobel Prize in Chemistry in 1990, and the American Chemical Society's greatest honor, the Priestley Medal, in 2004.
Major contributions
Reagents
Corey has developed several new synthetic reagents: PCC (pyridinium chlorochromate), also referred to as the Corey-Suggs reagent, is widely used for the oxidation of alcohols to corresponding ketones and aldehydes. PCC has several advantages over other commercial oxidants. An air-stable yellow solid, it is only slightly hygroscopic. Unlike other oxidizing agents, PCC requires only about 1.5 equivalents to complete a single oxidation (scheme 1).
In the reaction, the alcohol nucleophilically displaces chlorine from the electropositive chromium(VI) metal. The chloride anion then acts as a base to afford the aldehyde product and chromium(IV).
The slightly acidic character of PCC makes it useful for cyclization reactions with alcohols and alkenes (Scheme 2).
The initial oxidation yields the corresponding aldehyde, which can then undergo a Prins reaction with the neighboring alkene. After elimination and further oxidation, the product is a cyclic ketone. Conversely, powdered sodium acetate co-reagent inhibits reaction after formation of the aldehyde.
PCC's oxidatory robustness has also rendered it useful in the realm of total synthesis (Scheme 3). This example illustrates that PCC is capable of performing a Dauben oxidative rearrangement with tertiary alcohols through a [3,3]-sigmatropic rearrangement. t-Butyldimethylsilyl ether (TBS), triisopropylsilyl ether (TIPS), and methoxyethoxymethyl (MEM) are popular alcohol protecting groups. The development of these protecting groups allowed the synthesis of several natural products whose functional groups could not withstand standard chemical transformations. Although the synthetic community attempts to minimize the use of protecting groups, it is still rare that a published natural-product synthesis omits them entirely.
Since 1972 the TBS group has become the most popular silicon protecting group (Scheme 4). TBS is stable to chromatography and labile enough to cleave under basic and acidic conditions. More importantly, TBS ethers are stable to such carbon nucleophiles as Grignard reagents and enolates.