Related Experiment Video
Updated: Jan 9, 2026

Negative Additive Manufacturing of Complex Shaped Boron Carbides
Published on: September 18, 2018
Atomic-Level Insights into Thermal Carbonization of Ethynyl-Containing Boron Compounds
Kentaro Ohkura1, Satoshi Hayakawa2, Naoki Takahashi3
1Research Institute for Interdisciplinary Science, Okayama University, 3-1-1, Tsushimanaka, Kita-ku, Okayama, 700-8530, Japan.
None:
This study reports the design, synthesis, and characterization of boron-doped carbon (BDC) derived from a triethynylborane-pyridine complex. Triethynylborane is stabilized by coordination with pyridine, facilitating its synthesis and handling in ambient conditions. The complex is subjected to thermal treatment at various temperatures to form BDC. Powder XRD and single-crystal XRD analyses reveal that BDC prepared at 200 °C retains an ordered structure, while higher temperatures induce alkyne structural changes without significant weight or surface area alterations. Coin cells are assembled using BDC as the anode, demonstrating unique Li-ion and Na-ion storage properties distinct from graphite. These results suggest that the BDC reflects the precursor's crystal structure, enabling novel electrochemical behavior. These findings offer insight into the development of advanced BDC materials for energy storage applications.
Related Concept Videos
Hydroboration-Oxidation of Alkenes
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.
Regioselectivity and Stereochemistry of Hydroboration
Hydroboration proceeds in a concerted fashion with the attack of borane on the π bond, giving a cyclic four-centered transition state. The –BH2 group is bonded to the less substituted carbon and –H to the more substituted carbon. The concerted nature requires the simultaneous addition of –H and –BH2 across the same face of the alkene giving syn stereochemistry.
Cycloaddition Reactions: MO Requirements for Thermal Activation
Preparation of Alcohols via Addition Reactions
The acid-catalyzed addition of water to the double bond of alkenes is a large-scale industrial method used to synthesize low-molecular-weight alcohols. An acidic atmosphere is required to allow the hydrogen in the water molecule to act as an electrophile and attack the double bond in an alkene. The addition of a proton to the double bond creates a carbocation intermediate. The proton preferentially bonds to the less substituted end of the double bond to create a more stable carbocation...
Thermal Electrocyclic Reactions: Stereochemistry
Selection Rules: Thermal Activation
Conjugated systems containing an even number of π-electron pairs undergo a conrotatory ring closure. For example, thermal electrocyclization of (2E,4E)-2,4-hexadiene, a conjugated diene containing two π-electron pairs, gives trans-3,4-dimethylcyclobutene.

