page_title: Cyclobutanone
section_title: Preparation
hierarchical_section_title: Cyclobutanone / Preparation
context_page_description: Cyclobutanone is an organic compound with molecular formula (CH₂)₃CO. It is a four-membered cyclic ketone. It is a colorless volatile liquid at room temperature. Since cyclopropanone is highly sensitive, cyclobutanone is the smallest, easily handled cyclic ketone.
context_section_description: The Russian chemist Nikolai Kischner first prepared cyclobutanone in 1905.  He synthesized cyclobutanone in a low yield from cyclobutanecarboxylic acid in several reaction steps. This process is cumbersome and inefficient by today's standards.
  More efficient, high-yielding syntheses have since been developed. One strategy involves degradation of five-carbon building blocks. For example, the oxidative decarboxylation of cyclobutanecarboxylic acid was improved by the use of other reagents and methods. A newer, more efficient preparation of cyclobutanone was found by P. Lipp and R. Köster in which a solution of diazomethane in diethyl ether is reacted with ketene. This reaction is based on a ring expansion of the cyclopropanone intermediate initially formed, wherein molecular nitrogen is split off. The reaction mechanism was confirmed by a reaction using ¹⁴C-labeled diazomethane.
  Another synthesis of cyclobutanone involves lithium-catalyzed rearrangement of oxaspiropentane, which is formed by epoxidation of the easily accessible methylenecyclopropane.
  Cyclobutanone can also be prepared in a two step procedure by dialkylation of 1,3-dithiane with 1-bromo-3-chloropropane followed by deprotection to the ketone with mercuric chloride (HgCl₂) and cadmium carbonate (CdCO₃).
caption: Synthesis of cyclobutanone from cyclobutanecarboxylic acid