Year: 2025
Type: article
Abstract: Tightness engineering has evolved as an efficient strategy for the design of knotted, woven, and entangled molecules and materials with desired properties and functions since tightness is a primary parameter that determines the property of a knotted strand. However, as an attractive topic that inspires mathematicians, physicists, chemists, and biologists, whether the smallest knot is exactly the tightest one remains unaddressed experimentally. To tackle this challenge, a series of organic trefoil knots with the backbone-atom as short as 70 have been successfully synthesized by developing a new modular self-assembly approach in this study. To our great surprise, with the help of gradient tandem mass spectrometry, the quantitative tightness evaluation suggested that the molecular trefoil knot with a backbone crossing ratio (BCR) of 24.0 is even tighter than the one with a BCR of 23.3 (i.e., the smallest organic trefoil knot with the shortest ropelength synthesized so far), thus demonstrating an unexpected yet interesting odd-even effect to enhance the understanding of the tightness regulation of molecular knots.
Language: English
Subfield: Organic Chemistry
Field: Chemistry
Domain: Physical Sciences
Open Access status: bronze
OpenAlex ID: W4411610743