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Title: On the road to stable, isolable [4]cumulenes: Reactivity and cyclization reactions

The design and synthesis of persistent tetraaryl[4]cumulenes are reported. Derivatives with phenyl endgroups ([4]Phand[4]Ph/Ar*) are susceptible to reactions during synthesis and/or purification that complicate isolation of the desired product, particularly intermolecular dimerization reactions. Incorporation of (3,5‐di‐tert‐butyl)phenyl endgroups (Ar*) provides increased stability, culminating in the stable and isolable [4]cumulene[4]Ar*. Cumulene[4]Ar*remains, however, susceptible to dimerization under pressing conditions, and[4]Ar*also readily reacts with electrophiles under mild conditions that lead to intramolecular cyclization. Given the structural complexity of the side products in these studies (compounds3,10,14,17,18), X‐ray crystallography plays a vital role in their identification.

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Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Journal of Physical Organic Chemistry
Medium: X
Sponsoring Org:
National Science Foundation
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    Basic Protocol: Synthesis, deprotection, cleavage, and purification of sensitive oligodeoxynucleotides

    Support Protocol 1: Synthesis of Dim‐Dmoc nucleoside phosphoramidites

    Support Protocol 2: Preparation of CPG with a Dmoc linker

    Support Protocol 3: Synthesis of a phosphoramidite containing a sensitive alkyl ester group

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