Principles for Synthetic Efficiency and Expansion of the Field

Ring contraction in synthesis of functionalized carbocycles

“…Historically, low synthetic efficiency made these practically useful but synthetically challenging small carbocycles 32 inaccessible. Although various synthetic strategies have been proposed to improve the efficiency of synthetic design, [33][34][35][36][37][38][39][40][41] and contractive synthesis of carbocycles has seen wide application organic chemistry, they are still often overlooked (Scheme 1(C)).…”

Asymmetric Total Synthesis of the Rearranged Steroid Phomarol Enabled by a Biomimetic SN2′ Cyclization

“…Our retrosynthetic analysis, outlined in Scheme , was guided largely by Jung’s biosynthetic proposal for the formation of the TPR, as well as by our interest in utilizing sitolactone ( 20 ) as a chiral pool starting material for the construction of 6/5-fused ring systems . To maximize the synthetic efficiency, we sought to build the pentacyclic core framework by means of a convergent fragment-coupling approach . Specifically, disconnection of the central benzene ring via 6π electrocyclization and Suzuki coupling led to enol triflate 16 and vinyl boronate 17 .…”

Selectivity: A Goal for Synthetic Economy

“…2 Chemists are thus focused on designing efficient and benign synthetic routes to complex molecules and natural products in the most selective manner possible. 3 Although, it is quite challenging to achieve selectivity at times it is regarded as 'conditio sine qua non' (an indispensable condition) for highly reliable, easy to apply, simple to implement strategies with a high degree of efficiency and flexibility in terms of substrate scope.…”