Related Experiment Video
Updated: May 15, 2026

Facile Preparation of Ultrafine Aluminum Hydroxide Particles with or without Mesoporous MCM-41 in Ambient Environments
Published on: May 11, 2017
Mechanistic investigations of Al(OH)₃ oligomerization mechanisms
Xueli Cheng1, Wenchao Ding, Yongjun Liu
1School of Chemistry and Chemical Engineering, Taishan University, Tai'an 271021, China.
Abstract:
Aluminum aerogels have extremely low thermal conductivities, and are ideal candidates for use in thermal superinsulators, adsorbents, sensors, catalyst carriers, and inorganic fillers. In the present work, the oligomerization mechanisms of Al(OH)3 were investigated systematically with the Gaussian 03 package at the B3LYP/6-311++G(d,p) level in combination with CPCM single-point energy calculations. The results of our theoretical model showed that: (1) the Al atoms are tetracoordinate and pentacoordinate; (2) in alkaline solution, Al(OH)3 tends to condense into more soluble polyhydroxy compounds; (3) the neutral dimerization of Al(OH)3 and the transfer of the hydrogen on the bridging hydroxyl are energetically favorable, but the most stable geometry is a four-membered Al-O ring structure linked by two bridging hydroxyls; (4) Al(OH)3 is inclined to form tetracoordinate oligomers, which develop into three-dimensional structures connected by four-membered Al-O rings.
Related Concept Videos
Radical Anti-Markovnikov Addition to Alkenes: Mechanism
The mechanism starts with chain initiation, which involves two steps. In the first chain initiation step, a weak peroxide bond is homolytically cleaved upon mild heating to form two alkoxy radicals. In the second initiation step, a hydrogen atom is abstracted by the alkoxy radical...
Hydroboration-Oxidation of Alkenes
Radical Chain-Growth Polymerization: Mechanism
Alkynes to Aldehydes and Ketones: Hydroboration-Oxidation
One of the convenient methods for the preparation of aldehydes and ketones is via hydration of alkynes. Hydroboration-oxidation of alkynes is an indirect hydration reaction in which an alkyne is treated with borane followed by oxidation with alkaline peroxide to form an enol that rapidly converts into an aldehyde or a ketone. Terminal alkynes form aldehydes, whereas internal alkynes give ketones as the final product.
Oxidation of Alkenes: Syn Dihydroxylation with Osmium Tetraoxide
Alkenes via Reductive Coupling of Aldehydes or Ketones: McMurry Reaction
