Spiro-C(sp³)-atom transfer: Creating rigid three-dimensional structures with Ph₂SCN₂

Area of Science:

• Synthetic organic chemistry
• Three-dimensional molecular architectures

Background:

• Traditional methods often yield flat organic molecules with unsaturated carbon centers (C(sp)).
• Creating three-dimensional structures with a single quaternary carbon center (C(sp³)) is a significant synthetic challenge.

Purpose of the Study:

• To develop a general method for synthesizing molecules with C(sp³) quaternary centers.
• To introduce a novel reagent combining sulfur ylide and diazo compound reactivity.

Main Methods:

• Synthesis and application of the diazosulfur ylide reagent, Ph2S=CN2.
• Sequential or single-step installation of a C(sp³) atom to form spiro-centers.
• Exploration of C-C and C-X (X=O, N) bond formation around the C(sp³) center.

Main Results:

• General access to carbon spiro-centers via a C(sp³) atom installation.
• Formation of up to four C-C sigma bonds in a single step without transition metal catalysis.
• Synthesis of strained (oxa)spiro[2.2]pentanes and tricyclic spiro-compounds.

Conclusions:

• The Ph2S=CN2 reagent provides a versatile route to complex 3D organic structures.
• This method overcomes limitations in constructing quaternary carbon centers, expanding synthetic possibilities.