Semester-3 Unit-2 Fundamentals of Organic Chemistry Baeyer Strain Theory Adolf von Baeyer (a Nobel prize winner) proposed a theory in 1885 to explain the relative stability of the first few cycloalkane. The theory based on following facts: 1. Cyclo-alkanes are saturated compounds. So, all the carbons should have normal tetrahedral angle of 109 o 28 1 (or 109 o 5 1 ). 2. Any deviation of bond angles from the normal tetrahedral value would, impose a condition of internal strain on the ring called bond angle strain or Beayer strain 3. Higher value of angle strain of cycloalkane shows instability. As instability increases reactivity also increase. 4. If all the rings in cycloalkanes assumed to be planar, the bond angle strain for each ring can be calculated below . 5. According the above table smaller ring compounds cyclo propane and cyclobutane suffer large distortion and believed to be the cause of grater instability and enhanced r...
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