Classroom In this section of Resonance

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1 Classroom In this section of Resonance, we invite readers to pose questions likely to be raised in a classroom situation. We may suggest strategies for dealing with them, or invite responses, or both. Classroom is equally a forum for raising broader issues and sharing personal experiences and viewpoints on matters related to teaching and learning science. Card Games and Chemistry Teaching Organometallic Reactions Through Card Games We present a card game suitable for classroom use to provide an interactive and lively experience while studying organometallic reactions, synthesis and catalysis. It is based on a deck of playing cards, and we call it CARS (Catalysis and Reaction Sequences). The object is to arrange a set of random cards served to the player in a correct sequence. The correct sequence is based on the sequence of steps found in the catalytic cycle of a set of reactions. The game is similar to the popular multiplayer card game rummy. We illustrate the game with a set of cards based on the C C bond forming reactions, but it can be modified by the teacher to suit the topics being taught and could even be converted to a web-based version or a stand-alone study tool operating on a computer. A G Samuelson Department of Inorganic and Physical Chemistry Indian Institute of Science Bangalore , India. ashoka@iisc.ac.in Introduction Systematization and teaching of inorganic and organometallic chemistry reactions are daunting tasks. Teachers and students are bogged down by the prospect of studying literally hundreds of seemingly unrelated reactions. Anything that facilitates this process and helps in visualizing relationships is welcome. If one understands for example, how several organometallic reactions Keywords Catalysis, organometallic chemistry, card games, fun in chemistry. RESONANCE August

2 By writing the catalytic cycles presented in organometallic chemistry as a set of sequential reactions, it is possible to see that many reactions indeed follow a pattern. follow a common pattern in catalytic and stoichiometric reactions, it would be a great help to the student and teacher alike. By writing the catalytic cycles presented in organometallic chemistry as a set of sequential reactions, it is possible to see that many reactions indeed follow a pattern. It becomes easier for the student to connect a large number of reactions and attempt the construction of new catalytic cycles, given the reactants and products. Games have been used effectively for enhancing student involvement and making the student-teacher interaction more enjoyable than lecture-based classes [1]. In the past, games have aided chemical education especially in the nomenclature of compounds, study of elements in the periodic table and reactions [2]. Some of them are indeed card games to aid the study of nomenclature [3], formulas [4] and even improve the understanding of stereochemistry [5]. Recently, there have been some excellent descriptions of card games for teaching functional groups in organic chemistry [6], synthetic organic chemistry [7, 8], and one to teach retrosynthetic analysis [9]. We believe an extremely simple and general version of the popular card game rummy can be devised to learn organometallic chemistry and catalysis. We will illustrate the idea using a set of cards based on organometallic catalytic cycles using organic/organometallic synthesis. They are only illustrative and the game is designed in such a way that it can be used in different learning/teaching situations wherever a sequence of events is part of the learning objective. The deck of cards is patterned after the familiar 54 cards in common card games. The cards are divided into four groups or suits, each one representing a catalytic cycle (as in spades, clubs or clovers, diamonds and hearts). The name of each reaction is printed on a color-coded card and the substrates, products and reagents, if any, in that reaction are printed in the same color. The transformations or steps in the reaction can also be made into cards indicative of the reaction type such as oxidative addition, insertion or transmetallation, reductive elimination, ligand dissociation, etc. Each reaction cycle is thus mapped into a set of RESONANCE August 2018

3 cards. In order to increase the element of fun, one card, designated as a wild or special card, is included in each suit, and this maybeusedtofill in any part of the sequence. Two additional cards are generic multicolored wild cards that can be used for any reaction (across suits), reagent or sequence, making a total of 54 cards. Although the popular game of rummy is suggested, other games could be devised as well as the cards map to a regular pack of 54 cards in a deck. We will illustrate how this game can be used to teach/learn several C C bond forming reactions where the catalytic cycles bear some resemblance. When the catalytic cycles are grouped together in this fashion, the similarities and differences are brought out, and student understanding is significantly enhanced during the play. We have chosen four named reactions: HECK, NEGISHI, SUZUKI and SONOGHASHIRA. Each of these named reactions has a well-established catalytic cycle. Apart from the fact that the common catalyst of choice is a palladium complex, three of these reactions proceed through steps that are similar in the beginning and inthe end. TheHeck reaction has significant differences. The game allows the students to recognize the similarities and appreciate the differences. If the game is played in class after these reactions are taught, or right after the lecture in a tutorial class, it is easy for students to recollect these steps. It also allows the student to construct new cycles for reactions they encounter in the literature with ease. Figure 1 shows the catalytic cycle for the Heck reaction and Figure 2 shows the representative cards one can generate from this cycle. A similar exercise with the other three reactions would yield the requisite number of cards. A complete set of 54 cards is given in the supplementary section for the four reactions mentioned above. These card sets are only illustrative. Any four reactions could be substituted for these C C bond-forming reactions. One only needs to simplify the steps so that the reaction is completely represented by 12 to 13 cards. In order to play the game with two to four people, one pack of cards is thoroughly shuffled to generate a random set and each RESONANCE August

4 player is dealt a set of 10 cards. The remaining cards are kept aside face down as the stockpile. Each player tries to arrange the ten cards (s)he has according to a reaction sequence. The object of the game is to be the first one to arrange all the cards in valid sequences. Valid sequences could be formed as a sequence of 10 cards from one complete catalytic cycle (same color cards). Wild or special cards are permitted. If they are two different sequences they could be from two different catalytic cycles of say, a set of 7 in one cycle and a set of 3 from another, or even three different sequences of 3, 3 and 4. Players get to draw from the stockpile and discard unwanted cards until they can form sequences. In our experience, sequences are generated by at least one player within minutes. After the winner is confirmed, every player shows their sequences to other players and then a lively discussion follows. In one group, the students helped one another form all four sequences further reinforcing the learning experience. Although we emphasize the similarity with numbered cards, a caveat must be added. Sequences in CARS could have some differences from the classic card sequences. For example, in a reaction of A + B transformed by a substitution reaction R to give C + D; the sequence could be cards corresponding to A, B, R or B, A, R or R, C, D or R, D, C. All of them are chemically meaningful. However, the sequence B, R, and C is not considered a valid reaction sequence although based on numbers it is a valid sequence. Rules regarding this must be announced before starting the game. A player can choose to put down a run or sequence of three (minimum), four or seven cards in the centre of the playing area. This might allow another player to continue the catalytic sequence by adding a set. A player can choose to put down a run or sequence of three (minimum), four or seven cards in the centre of the playing area. This might allow another player to continue the catalytic sequence by adding a set. The object of the game is to help the students build the catalytic cycle or parts of it using the cards. So putting down the sequences as and when they form could help them recognize the catalytic cycles, the reactions and the substrates. This may increase the educational value. When played in this fashion, the person who puts down all the cards first wins. However, as a matter of strategy, many players choose not to put it down! 918 RESONANCE August 2018

5 Figure 1. The catalytic cycle of the Heck reaction: (LD = ligand dissociation; OA = oxidative addition; LS = ligand substituttion; MI = migratory insertion; HE = β- hydride elimination; RE = reductive elimination. The student learns different aspects of a catalytic cycle such as the requirement for a vacant site, a suitable oxidation state, matching substrates and catalysts in a lively environment. In the first few rounds of the game, students may be permitted to use their class notes or even have access to complete catalytic cycles. If needed, an easier card set could be printed with suitable hints on the cards suggesting what reactions are possible for the substrate or what substrates are suitable for the reaction. In an electronic version of the game, this could be made easier through the use of help files or simpler card sets. In order to play this game to aid self-study, one can play the equivalent of a Single Suit Spider. Multiple copies, usually eight, of the same (reaction) colored cards are needed to play this game. Both Rummy and Spider are readily played with these cards, and hence the games should be transferable to soft versions. Similarly, with some modifications, a board game like Snakes and Ladders could be constructed using the sequence. Board games RESONANCE August

6 Figure 2. Representative cards generated from the Heck reaction cycle presented in Figure 1. have the advantage that they could even be elaborated into social games such as Farmville. The framework described here is also suitable for further elaboration by increasing the difficulty level, and adding gaming elements so that a full-fledged gaming experience can be incorporated in the future. Converting the game into an app suitable for the mobile, or a web-based program independent of device architecture should also help more students to participate. If a gaming environment is provided, additional motivational aspects can set in, such as the desire to role play, gaining social recognition, a sense of accomplishment, handling challenges, mystery and fun that can lead to interactive and enjoyable learning. An excellent opportunity for gamification of 920 RESONANCE August 2018

7 Figure 3. Set of 54 cards suitable for printing on a plastic sheet. To download a set of printable cards please visit: learning exists [10]. We believe the incorporation of such games either through physical cards/boards or even through computer games or apps will improve the motivation and engagement of students. Conclusions Teaching organometallic reaction mechanisms and catalytic cycles using card games, in a fun-filled interactive setting is more effective than a slide presentation or even a chalk and board lecture. Since the game is tunable, it is likely to be of great value in teaching other topics where sequences are involved: such as in total synthesis. We have described here a general framework for converting any complex reaction with multiple steps into a card game very similar to rummy, the popular game of cards. Many opportunities open up once the teacher converts the learning objective into a game [11]. Supporting Information This section illustrates the set of 54 cards (Figure 3) suitable for printing on a plastic sheet. The sequence number is printed below the cards for the teacher s reference. Detailed instructions for playing the game is as follows. RESONANCE August

8 Instructions for Playing the Card Game CARS In order to play the game with four people, the cards are thoroughly shuffled to generate a random set and each player is dealt a set of 10 cards. The remaining cards are kept aside face down as the stockpile. The first player, takes a card from the stock and attempts to improve on the number of sequences (s)he has in hand (10 cards), and then discards any unwanted card with its face up. The next player in a similar fashion can take one card (DRAW) from the top of the stock or the card that was discarded by the previous player. However, each player must put back (DISCARD) the most unwanted card from her/his cards, or the card that was taken from the stock. So, at any stage of the game except during the player s turn, one has only 10 cards on hand. When one player finally forms three sequences, (s)he is declared the winner. If the stock isexhausted, the setofopen cardsareshuffled and replaced face down to form a fresh stock to continue the game. Acknowledgments The author thanks the students of the organometallic course who have participated in the game and several faculty members of IITs who have given valuable feedback. Suggested Reading [1] M J Samide, A M Wilson, Games, Games, Games; Playing to Engage with Chemistry Concepts, Chem. Educ., Vol.19, pp , [2] J V Russell, Using Games to Teach Chemistry: An Annotated Bibliography. J. Chem. Educ., Vol.76, pp , [3] R S Sevcik, L D Schultz, S V Alexander, Elements A Card Game of Chemical Names and Symbols, J. Chem. Educ., Vol.85, pp , [4] T A Morris, Go Chemistry: A Card Game to Help Students to Learn Chemical Formulas, J. Chem. Educ., Vol.88, pp , [5] M J Costa, Carbohydeck: A Card Game To Teach the Stereochemistry of Carbohydrates, J. Chem. Educ., Vol.84, pp , [6] M J Welsh, Organic functional Group Playing Card Deck, J. Chem. Educ., Vol.80, pp , RESONANCE August 2018

9 [7] C A Knudtson, ChemKarta: A Card Game for Teaching Functional Groups in Undergraduate Organic Chemistry, J. Chem. Educ., Vol.92, pp , [8] S C Farmer, M K Schuman, A Simple Card Game to Teach Synthesis in Organic Chemistry Courses, J. Chem. Educ., Vol.93, pp , [9] J M Carney, Retrosynthetic Rummy: A Synthetic Organic Chemistry Card Game, J. Chem. Educ., Vol.92, pp , [10] Y-k Chou, Actionable Gamification: Beyond Points Badges and Leaderboards, Octalysis Media, Freemont, [11] M Antunes, M A R Pacheco, M Giovanela, Design and Implementation of an Educational Game for Teaching Chemistry in Higher Education, J. Chem. Educ., Vol.89, pp , RESONANCE August