Molecular Synthesis, Structure, and Bonding
From the early days of the Chemical Revolution, scientists concerned themselves with how and why compounds form. Jöns Jakob Berzelius, for example, working in the first half of the 19th century, proposed that compounds were formed from atoms because of opposite electrical charges. This theory, called dualism, worked quite well, except in the emerging realm of organic chemistry; it could not explain the enormous number of compounds that were formed from four elements alone—carbon, oxygen, hydrogen, and nitrogen. More than a century of work by organic chemists explained this variety through new theories of molecular structure and bonding, theories that in time were transferred to the rest of chemistry. Critical to this progress were increasingly complex chemical analyses and syntheses, eventually aided by physical means like X-ray crystallography.
Justus von Liebig and Friedrich Wöhler were friends who helped make organic chemistry a field of systematic study within the framework of known chemical laws.
In 1856, 18-year-old William Henry Perkin synthesized mauve, or aniline purple—the first synthetic dyestuff. From this modest beginning grew the highly innovative chemical industry of synthetic dyestuffs and its near relative, the pharmaceutical industry.
In 1858 August Kekulé and Archibald Scott Couper independently recognized that carbon atoms can link directly to one another to form carbon chains. This finding explained the very multiplicity of carbon compounds that had been puzzling chemists.
Jacobus Henricus van’t Hoff was a pioneer in the field of stereochemistry, which deals with the spatial arrangements of atoms within molecules. He was also a founding father of physical chemistry and the recipient of the very first Nobel Prize in chemistry (1901).
Emil Fischer is noted for his work on purines, sugars, proteins, and their structures. He received the Nobel Prize in chemistry in 1902.
Gilbert Newton Lewis was instrumental in developing a bonding theory based on the number of electrons in the outermost “valence” shell of the atom.
Though he is perhaps best known to the public for his championing the use of vitamin C for health purposes, or for his Nobel Peace Prize, Linus Pauling was a prolific researcher who made significant contributions to our understanding of chemical bonding and structure, earning him a Nobel Prize for chemistry as well.
In the late 1930s Dorothy Crowfoot Hodgkin became a leading practitioner of the use of X-ray crystallography in determining the three-dimensional structure of complex organic molecules. She was the third woman ever to win the Nobel Prize in chemistry.
Robert Burns Woodward was a consummate master of synthetic organic chemistry who applied an uncanny intuitive sense of what was possible in the molecular world, as if he lived there part of the time. His most complex synthesis was vitamin B12.