B.S. Chemistry, University of North Carolina-Greensboro, 1979 M.S. Chemistry, Princeton University, Princeton, NJ, 1980 Ph.D. Chemistry, Princeton University, Princeton, NJ, 1983

Organic Chemistry

Research in the Herndon group focuses on the discovery of new organotransition metal-based processes for use in organic synthesis. Of specific interest are reactions that transform simple starting materials into complex products in a general, predictable, efficient, and stereoselective manner. Most of our present activity involves exploration of the coupling reaction between Fischer carbene complexes and highly conjugated acetylene derivatives. Several useful processes have been identified from these studies, and two of the systems under study are detailed below. The coupling of Fischer carbene complexes with enyne-aldehydes results in furan derivatives (eq 1). The unstable isobenzofuran ring system can be generated using benzo analogs (eq 2). Although unstable, this ring system very predictably undergoes Diels-Alder reactions. This reaction sequence serves as the cornerstone for preparation of pharmaceutically important structures (e.g. the estrogen-like structure depicted in eq 3) from two relatively simple components.

JWHrschsynop1

The coupling of Fischer carbene complexes with dienynes results in the synthesis of the benzofuran ring system (eq 4). This process has been found to be very and general and tolerant of a variety of substitution patterns. Numerous medicinally important compounds contain the benzofuran ring system and current research activity involves the synthesis of biologically active compounds for medicinal evaluation.

Herndon, J. W. “Annual Survey of the Carbon-Transition Metal Double and Triple Bond for the Year 2005.” Coord. Chem. Rev. 2009, 253, In Press

Herndon, J. W. Article entitled “Pentacarbonyl(methoxymethylcarbene)-chromium” for Encyclopedia of Reagents for Organic Synthesis. In Press

Zhang, Y.; Irshaidat, T.; Wang, H.; Waynant, K. V.; Wang, H.; Herndon, J. W. “Coupling of Fischer carbene complexes with conjugated enediynes featuring radical traps; Novel structure and reactivity features of chromium complexed arene diradical species.” Journal of Organometallic Chemistry 2008, 693, 3337-3345.

Duan, S.; Sinha-Mahapatra, D. K.; Herndon, J. W. “Synthesis of naphthalenes through three-component coupling of alkynes, Fischer carbene complexes, and benzaldehyde hydrazones via isoindole intermediates.” Org. Lett. 2008, 10, 1541-1544.

Herndon, J.W. “Annual Survey of the Carbon-Transition Metal Double and Triple Bond for the Year 2005.” Coord. Chem. Rev. 2009, 253, 86-179

Chen, Y.; Ye, S.; Jiao, L.; Liang, Y.; Sinha-Mahapatra, D. K.; Herndon, J. W.; Yu, Z. X.*, “Mechanistic Twist of the [8+2] Cycloadditions of Dienylisobenzofurans and Dimethyl Acetylenedicarboxylate: Stepwise [8+2] vs. [4+2]/[1,5]-Vinyl Shift Mechanisms Revealed Through a Theoretical and Experimental Study.” J. Am. Chem. Soc. 2007, 129, 10773-10784.

Menon, S.; Sinha-Mahapatra, D.; Herndon, J. W. “Synthesis of phenanthrene derivatives through the net [5+5]-cycloaddition of prenylated carbene complexes with 2-alkynylbenzaldehyde derivatives.” Tetrahedron, 2007, 63, 8788-8793.

Herndon, J.W. “Annual Survey of the Carbon-Transition Metal Double and Triple Bond for the Year 2005.”Coord. Chem. Rev. 2007, 251, 1158-1258.

Duan, S.; Cress, K.; Waynant, K.; Ramos-Miranda, E.; Herndon, J. W. “Synthesis of alkylidenephthalans through fluoride-induced cyclization of electron-deficient 2-siloxymethylphenylacetylene derivatives.” Tetrahedron 2007, 63, 2959-2965.