Professor Seyferth’s research during the past forty years has been in the general area of organometallic chemistry of the main group elements (principally Li, Mg, Zn, Hg, B, Si, Ge, Sn, Pb and P) and transition metals (principally Co and Fe). The work has dealt with the synthesis and characterization of organometallic compounds, their reactivity (including mechanistic studies) and their applications, mainly in organic synthesis and materials chemistry. Recent work has in part dealt with the development of polymeric precursors whose pyrolysis results in useful nonoxide ceramics such as silicon carbide, nitride, carbonitride and oxynitride, boron nitride, aluminum nitride, as well as carbides, nitrides, silicides and borides of the early transition metals.

Major research achievements are summarized below.

Major research achievements:

1. Development of practical and broadly applicable routes for the synthesis of useful functional organolithium reagents via transmetalation reactions of heavy metal (Sn, Pb) organometallics, including vinylic and allylic lithium reagents, Ph2P(X)-CH2Li (X = O, S) and acyllithium reagents, RC(O)Li, which were prepared in situ by the carbonylation of RLi at -110°C. The methodology involved has been widely used by others in organic synthesis, especially for CH2=CHLi and CH2=CHCH2Li.
   
   SELECTED REFERENCES:
   J. Am. Chem. Soc., 83 (1961) 3583.
   J. Org. Chem., 45 (1980) 2273.
   Israel J. Chem., 24 (1984) 167.
   J. Org. Chem., 56 (1991) 5768.
   
   
2. Development of the phenyl(trihalomethyl)mercury reagents, PhHgCX3 (especially PhHgCCl2Br, PhHgCBr3, and PhHg CF3), as dihalocarbene precursors. Thermolysis of such reagents at 60-80°C provides a "clean" source of CCl2 and CBr2, so that CX2 insertion even into unactivated paraffinic C–H bonds can be effected. Broad synthetic applications in organic and organometallic chemistry.
   
   REFERENCE:
   Acct. Chem. Res., 5 (1972) 65 (Review).
   
   
3. Broad development of the organic chemistry of RCCo3(CO)9 cluster complexes including the ability of the CCo3(CO)9 cluster to stabilize an adjacent carbonium and acylium ion positively charged center.
   
   REFERENCE:
   Acct. Chem. Res., 5 (1972) 65 (Review).
   
   
4. Preparation and isolation of the first silacyclopropanes and silacyclopropenes and development of the unusual chemistry of these highly strained and hyperreactive silacycles, including the application of hexamethylsilacyclopropane as a practical dimethylsilylene precursor for use under mild conditions.
   
   REFERENCE:
   J. Organomet. Chem., 100 (1975) 237 (Review).
   
   
5. Development of the chemistry of (µ-S2)Fe2(CO)6, an inorganic mimic of organic disulfides and a precursor for the useful (µ-S–)2Fe2(CO)6 anion (a sulfur nucleophile) and of the versatile [(µ-CO)(µ-RS)Fe2(CO)6]– anions (iron-centered nucleophiles).
   
   SELECTED REFERENCES:
   Organometallics, 1 (1982) 125.
   Organometallics, 8 (1989) 430.
   Organometallics, 9 (1990) 2662.
   Organometallics, 10 (1991) 3363.
   J. Am. Chem. Soc., 114 (1992) 4594.
   
   
6. Generation of useful non-oxide ceramics such as SiC, Si3N4, silicon carbonitride and BN by pyrolysis of suitable processable polymeric precursors. This involved synthesis of new types of organosilicon and boron polymers with latent (reactive) functionality suitable for thermal crosslinking, so that on pyrolysis high yields of ceramics can be obtained and the destructive effect of evolved gases minimized. Pyrolysis mechanism studies. Chemical modification of existing preceramic polymers.
   
   REFERENCES:
   J. Am. Ceram. Soc., 71 (1988) C-194.
   J. Am. Ceram. Soc., 73 (1990) 2131.
   Chapter in "Silicon-Based Polymer Science" (Advan. Chem. Ser. 224), ACS, Washington, 1990, pp 565–591 (Review).
   J. Inorg. Organomet. Polym., 2 (1992) 59.
   J. Am. Ceram. Soc., 5 (1992) 75.
   
   
7. Preparation and functionalization of carbosilane dendrimers. Functionalization of the periphery of the dendrimers with:
   
   (a) Group 4 metallocene substituents to obtain catalysts for a-olefin polymerization.
   (b) Water-solubilizing groups (–SO3–Na+, –NHMe2+Cl–) to obtain synthetic micelles.
   (c) Tin hydride substituents (–SnBu2H) to obtain reagents useful for organic synthesis.
   
   REFERENCES:
   Organometallics, 13 (1994) 2682.
   Organometallics, 14 (1995) 5362.