TY  - JOUR
A1  - Wessig, Pablo
A1  - Krebs, Saskia
T1  - N-aroylsulfonamide-photofragmentation (ASAP)
BT  - a versatile route to biaryls
JF  - European journal of organic chemistry
N2  - The photochemical fragmentation of N-aroylsulfonamides 9 (ASAP) is a powerful method for the preparation of various biaryls. Compounds 9 are easily accessible in two steps from amines by treatment with arenesulfonyl chlorides and aroyl chlorides. Many of these compounds were prepared for the first time. The irradiation takes place in a previously developed continuous-flow reactor using inexpensive UVB or UVC fluorescent lamps. Isocyanates and sulphur dioxide are formed as the only by-products. The ASAP tolerates a variety of functional groups and is even suited for the preparation of phenylnaphthalenes and terphenyls. The ASAP mechanism was elucidated by interaction of photophysical and quantum chemical (DFT) methods and revealed a spirocyclic biradical as key intermediate.
KW  - Biaryls
KW  - Fragmentation
KW  - Isocyanates
KW  - Photochemistry
KW  - Sulfonamides
Y1  - 2021
U6  - https://doi.org/10.1002/ejoc.202100955
SN  - 1434-193X
SN  - 1099-0690
VL  - 2021
IS  - 46
SP  - 6367
EP  - 6374
PB  - Wiley-VCH
CY  - Weinheim
ER  - 
TY  - JOUR
A1  - Storch, Golo
A1  - Maier, Frank
A1  - Wessig, Pablo
A1  - Trapp, Oliver
T1  - Rotational Barriers of Substituted BIPHEP Ligands: A Comparative Experimental and Theoretical Study
JF  - European journal of organic chemistry
N2  - The interconversion barriers of 14 different 3,3- and 5,5-disubstituted tropos BIPHEP [2,2-bis(diphenylphosphino)-1,1-biphenyl] and BIPHEP(O) [2,2-bis(diphenylphosphoryl)-1,1-biphenyl] ligands were investigated by enantioselective dynamic high performance liquid chromatography (DHPLC) and DFT calculations using the B3LYP/6-31G* and M06-2X/6-31G* levels of theory. The experimentally determined enantiomerization barriers varied from 86.8 to 101.4 kJmol(-1) and were found to be in excellent agreement with the calculated data. The root-mean-square deviations are 7.3 kJmol(-1) for the B3LYP functional and 11.3 kJmol(-1) for the M06-2X method.
KW  - Rotational barriers
KW  - Density functional calculations
KW  - Enantioselectivity
KW  - P ligands
KW  - Biaryls
KW  - Liquid chromatography
Y1  - 2016
U6  - https://doi.org/10.1002/ejoc.201600836
SN  - 1434-193X
SN  - 1099-0690
VL  - 22
SP  - 5123
EP  - 5126
PB  - Wiley-VCH
CY  - Weinheim
ER  - 
TY  - JOUR
A1  - Schmidt, Bernd
A1  - Riemer, Martin
T1  - Synthesis of Magnaldehydes B and E and Dictyobiphenyl B by Microwave-Promoted Cross-Coupling of Boronophenols
JF  - European journal of organic chemistry
N2  - Magnaldehydes B and E along with their 4'-methylated derivatives are naturally occurring 2,4'-biphenols that have been isolated from the Magnoliaceae. Herein, these natural products have been synthesized from a common intermediate, which was obtained by a microwave-promoted, hetero-geneously catalyzed, and protecting-group-free Suzuki-Miyaura coupling reaction in an aqueous medium. These reaction conditions were also successfully applied to a one-step synthesis of the slime mold metabolite dictyobiphenyl B.
KW  - Total synthesis
KW  - Natural products
KW  - Cross-coupling
KW  - Palladium
KW  - Biaryls
KW  - Phenols
Y1  - 2015
U6  - https://doi.org/10.1002/ejoc.201500350
SN  - 1434-193X
SN  - 1099-0690
IS  - 17
SP  - 3760
EP  - 3766
PB  - Wiley-VCH
CY  - Weinheim
ER  - 
TY  - JOUR
A1  - Wessig, Pablo
A1  - Pick, Charlotte
A1  - Schilde, Uwe
T1  - First example of an atropselective dehydro-Diels-Alder (ADDA) reaction
JF  - Tetrahedron letters
N2  - A new concept of a stereoselective synthesis of axially chiral biaryls, formed in the course of the dehydro-Diels-Alder (DDA) reaction, has been disclosed. It is based on asymmetric induction of the newly formed chirality axis by a chirality center, which is present in the two synthesized DDA reactants. Depending on the different length of the linkers joining the alkyne moieties the DDA reaction may be triggered photochemically or thermally, where only the thermal variant was stereoselective.
KW  - Cycloaddition
KW  - Atropselecrivity
KW  - Biaryls
KW  - Alkynes
KW  - Photochemistry
Y1  - 2011
U6  - https://doi.org/10.1016/j.tetlet.2011.06.024
SN  - 0040-4039
VL  - 52
IS  - 32
SP  - 4221
EP  - 4223
PB  - Elsevier
CY  - Oxford
ER  -