Effectiveness of a 2-Cycle Organic Chemistry Sequence Doug Schirch BCCE, August 2010

2-Cycle Organic Chemistry Covers material from a standard 2-semester course in a different sequence: – First semester: Survey course of the fundamentals of organic chemistry (functional groups, nomenclature, major reactions, etc.) – Second semester: Builds on top of the first semester, more in-depth coverage, more rigorous.

Problems with Standard Sequence 1-semester students (Biology and Environmental Science majors; 40%) – Miss many functional groups common in nature (carboxylic acids, amides, esters, amines, etc.) – Forced to learn less relevant material All students: often can’t see the forest for the trees. Small schools can’t offer separate courses

With 2-Cycle Sequence 1-semester students: – Get a survey of the most pertinent organic chemistry. 2-semester students (Chem. majors and pre- professionals) : – Build a solid foundation in basic organic chemistry before engaging more advanced material. – In 2 nd semester, forced to recall 1 st semester material to build on it, resulting in better learning.

Outline 1.Background 2.Course content in each semester 3.My experiences 4.Results of standardized final exams before and after adopting a 2-cycle approach 5.Student opinions.

Background Previous publications: – Minter and Reinecke. J of Chem Ed. (1985), Vol. 62 At Texas Christian Univ. – Sartoris. J of Chem Ed. (1992), Vol. 69 At Wittenberg Univ. – Gravert. J of Chem Ed. (2006), Vol. 83 At St. Mary’s University of Minnesota

All 3 reported higher ACS scores after adopting 2-cycle approach Material covered in 1 st and 2 nd semesters … Textbook options – 1 st : Survey text, then 2 nd : 2-semester text – 2-semester text used both semesters – [Interested in a text for 2-cycle approach?] Number of schools using this approach?

Sequence I Use 1 st Semester2 nd Semester Review of bonding theories, EN, etc. Const. and geometric isomers, conformers, intro to chirality Intro. to all the major functional groups, their nomenclature, and properties Fundamental reactions for each functional group Limited mechanisms Some multi-step synthesis problems Lab: Standard purification techniques, TLC, melting points, a synthesis, GC-MS

Sequence I Use 1 st Semester2 nd Semester Review of bonding theories, EN, etc.Additional reactions Const. and geometric isomers, conformers, intro to chirality Additional mechanisms Intro. to all the major functional groups, their nomenclature, and properties More depth on nucleophilic substitution and chirality Fundamental reactions for each functional group More complex multi-step synthesis problems Limited mechanismsSpectroscopy Some multi-step synthesis problems Lab: Standard purification techniques, TLC, melting points, a synthesis, GC-MS Lab: Syntheses, literature project, qualitative analysis using MS, FT-NMR, FT- IR

My experiences: what worked, what didn’t Textbook: 2-semester Carey for both semesters Homework: – Submitted more frequently, but – Insufficient problems in 1 st semester sometimes In 2 nd semester students are stronger, better prepared, and have better study skills Weekly help sessions no longer needed Problematic for transfers (?)

Comparison of Scores on Standardized Final Exam at End of 2 nd Semester Standard sequence 2-cycle sequence

Comparison of Scores on Standardized Final Exam at End of 2 nd Semester Standard sequence 2-cycle sequence

Survey of Student Perceptions Survey sent to all previous students from the years a 2-cycle sequence used. – Of 31 one-semester students, 17 (55%) responded – Of 49 two-semester students, 30 (61%) responded

“I think it was good to have the first semester of the course be a general survey of organic chemistry that covers the fundamental topics relevant to biology.” 1-semester students 2-semester students Strongly Disagree16%0 Disagree00 Neither agree nor disagree 027% Agree635%1550% Strongly Agree1059%1343%

“I found it confusing to be skipping some chapters or sections in the textbook.” 1-semester students 2-semester students Strongly Disagree318%723% Disagree1165%1860% Neither agree nor disagree 212%310% Agree16%27% Strongly Agree00

“I think it would be better to follow the standard sequence, going through the first half of the text in the first semester and the second half of the text in the second semester..” 1-semester students 2-semester students Strongly Disagree318%827% Disagree1165%1550% Neither agree nor disagree 212%723% Agree16%0 Strongly Agree00

“For the content we covered in the first semester, I think I would have learned better with a smaller textbook designed for a 1-semester introduction to organic chemistry course, instead of the larger 2- semester text that we used parts of.” 1-semester students Strongly Disagree16% Disagree741% Neither agree nor disagree 635% Agree318% Strongly Agree0

“Instead of the large 2-semester text that we used for both semesters, I think I would have learned better with a smaller textbook designed for a 1-semester introduction to organic chemistry course in the first semester, and then only using the larger 2-semester text for the second semester.” 2-semester students Strongly Disagree517% Disagree1137% Neither agree nor disagree 723% Agree723% Strongly Agree0

“Seeing some material twice during the year (at an introductory level in the first semester and in more depth during the second semester) helped me learn the material better by the end of the course.” 2-semester students Strongly Disagree00% Disagree13% Neither agree nor disagree 13% Agree1240% Strongly Agree1653%

Summary 2-cycle sequence allows a much better experience for 1-semester students 2-semester students show increased learning and prefer the 2-cycle approach The most significant problems (lack of specific text and transfer students) are minor For copy of PowerPoint or more info: Questions??