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October 29, 2012: Just published in The Journal of Organic Chemistry as a Feature Article, work carried out with the groups of Profs. J. Morzycki in Poland and R. Santillan in Mexico describes an efficient seven-step synthetic route and the internal dynamics of two beautiful crystalline macrocyclic molecular rotors.
July 19, 2012: Aziridines crystals are “born” in a metastable form - The photodenitrogenation of crystalline triazolines generates the corresponding aziridines in nearly quantitative yields. Using powder X ray diffraction to monitor the photoreaction progress, it was shown that the packing structure of the starting material remains in the product obtained. The study is detailed in Denisse de Loera’s just published Organic Letters paper.
February 16, 2012: 2D Glasses!!! - Molecular rotors confined in two dimensions form rotational glasses and rotational liquids. Cortnie Vogelsberg's recent Journal of Physical Chemistry B article describes this phenomenon with p-divinylphenylene rotators in a hierarchically ordered periodic mesoporous organosilica. The study reveals non-Arrhenius dynamics and an increase in heat capacity characteristic of a phase transition. This unprecedented discovery is an exceptional platform for the development of hypersensitive thermally activated molecular machines. Congrats, Cortnie!
October 24, 2011: Cortnie Vogelsberg’s Chem. Soc. Rev. article “Crystalline molecular machines: function, phase order, dimensionality, and composition” is now available as an Advance Article here!  This thought provoking critical review is a great introduction to the developing field of amphidynamic molecular machines and their potential.  It is also a great read to catch up on the latest progress in the field.  Congrats, Cortnie!
research highlight picture.tiff September 23, 2011: How to cross three bridges in one step - A very nice synthetic strategy was devised to construct molecular gyroscopes with three bridges (shown in green) in only one step.  Their single crystal X-ray structures reveal that the molecular gyroscopes pack in ordered sheets, which will be ideal for structures with interacting polar rotators.  Read Patrick Commins’ and Jose Nunez’s synthetic strategy in the Journal of Organic Chemistry.
September 22, 2011:  The Case of the Short-Lived Triplets - Using transient spectroscopy to determine the excited lifetimes of nanocrystalline benzophenones, we determined why certain triplet states are extremely short lived in solids but not in solution.  The triplet excited states of the substituted benzophenones are quenched by an adjacent molecule in the ground state via a reductive charge transfer (CT) mechanism.  Hot off of the press, see the “just accepted” JACS full article describing Greg Kuzmanich and Matt Gard’s work in collaboration with the group of Prof. Guldi.
May 23, 2011:  Challenging Reactions Gone Green - Crystals of hexasubstituted ketones exposed to light, without solvents or any other reagents, give quantitative yields of products with all-carbon adjacent quaternary stereogenic centers, which are very difficult to obtain otherwise.  Crystalline ketones were easily generated by trapping tertiary carbanions with a carbonyl source and the subsequent solid-state reaction gave the product with complete diastereoselectivity.  The method developed by Saori Shiraki just appeared in Photochemical and Photobiological Sciences.
May 20, 2011: Life in the Fast Lane - Using ultrafast pulses to determine the excited kinetics of a nanocrystalline indanone, we discovered that the reaction in crystals can be very fast; starting with a singlet biradical, visting the triplet state, and then going on to the product in less than 10 nanoseconds. See the Chemical Science edge article describing Greg Kuzmanich's work in collaboration with Profs. Tito Scaiano, José-Carlos Netto-Ferrerria, and Matt Platz.
May 18, 2011:  First 1D rotor chain! - Collaborative studies bridged by Braulio Rodriguez-Molina between our group at UCLA and the Santillan group in CINVESTAV, Mexico, led to the discovery of the first crystalline array of molecular rotors that undergo correlated motions in a 1D chain.   Read this work in: J. Am. Chem. Soc., 2011, 133, 7280.
April 21, 2011: Towards Exploded Stators - Zach O'Brien's design and solid state NMR study of a new molecular gyroscope with "exploded" tri-(meta-terphenyl)methyl stators shows that steric bulk and rigidity yields robust yet low-density crystals capable of accommodating phenylene rotation in excess of 100 MHz at room temperature.
April 11, 2011: Add halogen-bonding to the toolbox of crystal engineering techniques for amphidynamic molecular machines. Cortnie Vogelsberg's solid-state NMR analysis of crystalline 1,4-bis(iodoethynyl)bicyclo[2.2.2]octane showed that halogen-bonded molecular rotors sustain ultra-fast rotation. This study, in collaboration with Prof. Stuart Brown and the group of Prof. Patrick Batail, validates an unprecedented approach to the construction of amphidynamic molecular machines where the extended framework itself provides the template to sustain engineered rotation to very low temperatures. See the ASAP JACS article here!
February 8, 2011: Oxyallyl is Blue! Even though oxyallyl is a ubiquitous reaction intermediate involved in many organic reactions, until now, it had resisted all attempts at direct detection, isolation, and characterization. See here the JACS communication describing Greg Kuzmanich's work in collaboration with the groups of Profs. Dirk M. Guldi and Kendall Houk.

 

March 16, 2010: Zach O'Brien's new article, "Solid-State Molecular Rotors with Perdeuterated Stators:Mechanistic Insights from Biphenylene Rotational Dynamics in Ordered and Disordered Crystal Forms," is now available on the Journal of Organic Chemistry website.

  March 16, 2010: Publications list updated.
Jan. 4, 2010: Our collaborative research on the direct detection of nanocrystalline radical pairs with the groups of Prof. Malcolm Forbes and Dr. Valery Tarasov published in the Journal of the American Chemical Society has been highlighted by Chemical and Engineering News.
  Nov. 2, 2009: Greg Kuzmanich was awarded the John Stauffer Award for Excellence in Research at the Department of Chemistry and Biochemistry Awards Ceremony. Congratulations, Greg!
Oct. 14, 2009: It was just announced that former group member Marcia Levitus (pictured below), now a professor at Arizona State University,is the winner of the 2010 Young Investigator Award of the Inter-American Photochemical Society. An excerpt from the award citation: "Prof. Levitus has established a leading research program in the area of biomolecular dynamics, using ultrasensitive fluorescence techniques to probe the biological implications of structural fluctuations in nucleosomes as well as to characterize the impact of covalent attachment on the fluorescent properties of dyes often used to label biomolecules." Congratulations to Marcia!
May 27, 2009: Computational predictions by Luis Campos, a synthetic method developed by Marino Resendiz, and remarkable analytical procedure developed by Farnosh Family are among the ingredients used in a recent Journal of the American Chemical Society article describing the first example of a radical pair reaction that occurs with a double memory of chirality.
April 20, 2009: The MGG group's P3 team, composed of Farnosh Family, Saori Shiraki and Greg Kuzmanich, received honorable mention for their design and proposal on eco-friendly, solvent-free synthesis of natural products at the Environmental Protection Agency's 2009 P3: People, Prosperity and the Planet Student Design Competition for Sustainability. Farnosh (pictured) presented the group's work in a poster at the competition, which took place in Washington, D.C., April 18-20, to coincide with Earth Day. Read their project abstract, and learn more about the 12 Principles of Green Chemistry and the American Chemical Society's Green Chemistry Institute.