Science, Tech, Math › Science Periplanar Definition in Chemistry Definition of Periplanar Print These structures show the sawhorse and Newman projections of two periplanar conformations of butane. Todd Helmenstine Science Chemistry Molecules Basics Chemical Laws Periodic Table Projects & Experiments Scientific Method Biochemistry Physical Chemistry Medical Chemistry Chemistry In Everyday Life Famous Chemists Activities for Kids Abbreviations & Acronyms Biology Physics Geology Astronomy Weather & Climate By Anne Marie Helmenstine, Ph.D. Anne Marie Helmenstine, Ph.D. Chemistry Expert Ph.D., Biomedical Sciences, University of Tennessee at Knoxville B.A., Physics and Mathematics, Hastings College Dr. Helmenstine holds a Ph.D. in biomedical sciences and is a science writer, educator, and consultant. She has taught science courses at the high school, college, and graduate levels. Learn about our Editorial Process Updated on January 12, 2020 Periplanar refers to two atoms or groups of atoms in a conformation are in the same plane with respect to the reference single bond. The image shows two conformations of butane (C4H10). The methyl groups (-CH3) are lined up in the same plane with the middle carbon-carbon single bond. The top conformation is known as syn-periplanar and the bottom is known as anti-periplanar. Sources March, Jerry (1985). Advanced Organic Chemistry: Reactions, Mechanisms, and Structure (3rd ed.). New York: Wiley. ISBN 0-471-85472-7.Testa, Bernard; Caldwell, John (2014). Organic Stereochemistry: Guiding Principles and Biomedicinal Relevance. ISBN 390639069. Cite this Article Format mla apa chicago Your Citation Helmenstine, Anne Marie, Ph.D. "Periplanar Definition in Chemistry." ThoughtCo, Aug. 27, 2020, thoughtco.com/definition-of-periplanar-603553. Helmenstine, Anne Marie, Ph.D. (2020, August 27). Periplanar Definition in Chemistry. Retrieved from https://www.thoughtco.com/definition-of-periplanar-603553 Helmenstine, Anne Marie, Ph.D. "Periplanar Definition in Chemistry." ThoughtCo. https://www.thoughtco.com/definition-of-periplanar-603553 (accessed April 20, 2024). copy citation