this project was developed 
 for the second semester of a two - semester , two - credit introductory 
 organic chemistry laboratory course sequence for chemistry and related 
 majors ; the project was first implemented in spring 2012 and successfully 
 improved for spring 2013 .
the course is separate from the pre- or 
 co - requisite organic lecture course and meets twice weekly for 3-h 
 sessions , in sections each led by a graduate teaching assistant ( ta ) . 
 typically , the student : ta ratio is less than 12:1 , and the course 
 consists of 5070% second - year students , with the remainder 
 being composed primarily of third - and fourth - year students . over the 
 two years
this project has been implemented , 40 students have participated . 
 for many students ,
the project could also be appropriate for an 
 upper - division undergraduate organic laboratory course . in developing the research 
 module ,
a primary goal was to introduce students to authentic organic 
 chemistry practice  a goal to which student attention was explicitly drawn .
this goal could be achieved by requiring 
 students to find , adapt , and optimize procedures directly from the 
 literature to develop and carry out a multistep synthesis . in so doing , 
 a secondary goal of exposure to modern synthetic techniques , including 
 microwave - accelerated synthesis and affinity chromatography ,
in particular , chromatography is an important part of 
 the everyday life of synthetic organic chemists , but relatively little 
 chromatography is carried out in organic teaching labs .
reasons for 
 this omission may include the safety issues of packing and running 
 columns with standard silica gel ( inhalation hazard ) in pressurized 
 glassware ( explosion hazard ) , as well as the cost of the silica gel 
 and solvent disposal for single - use columns . the use of fluorous affinity 
 chromatography with prepacked columns could make a chromatography 
 process more feasible in teaching labs : the preparation issues are 
 avoided , and the columns can be reused multiple times . moreover , an 
 understanding of affinity chromatography and noncovalent interactions 
 is particularly relevant for students who go on to pursue work in 
 biochemistry and areas of biology where it is a common technique .
fluorous chemistry is a rapidly growing subfield 
 of organic chemistry that has also gained attention in the context 
 of green chemistry .
this is due in part 
 to the recyclability of many fluorous - tagged reagents and catalysts , 
 as well as the fact that product isolation and purification using 
 fluorous tags is greatly facilitated .
the crux of the project reported 
 herein was to synthesize a brightly colored molecule bearing a fluorous 
 tag and then to use that product to explore fluorous solid - phase extraction 
 ( fspe ) so that the separation process 
 could be easily followed visually and understood conceptually .
the 
 project described is , to the best of our knowledge , the first reported 
 implementation of fluorous synthesis and solid - phase extraction chemistry 
 in the undergraduate organic teaching laboratory . in preliminary development , ways were sought to attach 
 a fluorous tag to fluorescein derivatives ; 
 a recent fluorescein experiment from this journal has already been successfully adopted in this course . after encountering difficulty
early in the development 
 phase for such a project , a fluorous aminoanthraquinone target was 
 selected ( scheme 1 ) .
the rationale for this 
 selection drew upon the precedent that compounds of type 1a ( r = ch2rf , x = f , where rf is 
 perfluoroalkyl ) are known to be useful molecules for visualizing fluorous 
 separations , whereas aminoanthraquinones 
 of type 1b ( r = alkyl or aryl , x = ots ) are known to 
 be easily accessed from a readily available , inexpensive starting 
 material ( quinizarin , 2 ) .
once the target was selected , 
 a route was devised that would require 
 students to engage in multistep synthesis .
after debate on how best 
 to frame the experience for the students , it was ultimately decided 
 to provide them with scheme 2 in its entirety 
 to facilitate their search for literature procedures to attempt directly 
 or to modify to their needs .
although explicitly told that they could deviate 
 from the provided scheme if desired , students generally opted to follow 
 the sequence shown .
several features of this route are noteworthy:all of the 
 intermediates except 
 the final product are known compounds , facilitating the literature 
 search process;it combines familiar , textbook 
 chemistry with challenging chemistry not typically found in traditional 
 undergraduate laboratory or lecture;the literature procedures that 
 are found as precedents for individual steps require modification 
 for use in the teaching laboratories due to constraints of time , equipment , 
 or reagent safety  requiring students to think critically about 
 them and to come up with viable alternatives .
all of the 
 intermediates except 
 the final product are known compounds , facilitating the literature 
 search process ; it combines familiar , textbook 
 chemistry with challenging chemistry not typically found in traditional 
 undergraduate laboratory or lecture ; the literature procedures that 
 are found as precedents for individual steps require modification 
 for use in the teaching laboratories due to constraints of time , equipment , 
 or reagent safety  requiring students to think critically about 
 them and to come up with viable alternatives .
it was anticipated that such a project design would provide 
 ample 
 opportunity for students to develop their own chemistry and attempt 
 to establish alternative reaction conditions for given transformations , 
 while minimizing the time , logistical , and safety issues that typically 
 accompany more open - ended projects .
early 
 in the semester , students began using scifinder scholar , were introduced to the project , and were provided 
 with scheme 2 .
students were told that they 
 would , on an individual basis , have to submit a proposal before they 
 began .
the proposal would contain literature procedures for their 
 reactions as well as their proposed modifications thereof ( based on 
 the rules below , vide infra ) .
after several weeks of planning outside 
 of class , students would be given six consecutive lab periods in which 
 to carry out their individual synthesis .
in the interim , students 
 would continue to do typical laboratory experiments , as well as inquiry - based 
 mini - projects that served to prepare them for 
 the capstone project .
additionally , students were given two lab periods 
 interspersed through the early part of the semester to ease into the 
 project and practice the literature search and independent work process 
 prior to the dedicated block of project time .
students were 
 free to explore any chemistry that they had found as precedent , within 
 the following constraints : ( 1 ) they would be allowed to leave reactions 
 unattended or heating over extended time periods , if desired , provided that they were properly labeled and that no reflux condenser 
 was required when the laboratory was unoccupied ; ( 2 ) particular 
 reactions that would require equipment that was unavailable to all 
 students ( a parr hydrogenation bottle ) and specific reagents ( such as bu3snh ) were labeled off - limits ; 
 ( 3 ) their scale would be limited to a few attempts at the use of one 
 gram of perfluorooctyl iodide in the conversion of 4 
  5 in 
 scheme 2 ; and ( 4 ) their procedures would be 
 vetted by the teaching staff after an inspection for safety considerations . 

it was anticipated that these few rules would force students to be 
 creative and to think critically about reaction design . at the same 
 time
, students would be able to experience a modicum of freedom and 
 thus take ownership of their project .
students were informed that another 
 way that the project mirrors the typical practice of organic chemistry 
 research is that the key intermediate , perfluorooctylpropyl amine 7 , is commercially available but at high cost .
a small amount 
 would be available to them if necessary to use on the final day of 
 the project , so that they could still perform the final synthetic 
 step and explore the fspe technique .
rather than diminish their motivation 
 or make them believe that this was an exercise in futility , this served 
 to ease the pressure they felt that they must be 
 able to make it to the end on their own in the time allotted ( eight 
 total lab periods ) .
this is fortuitous , because , to date , the long - term 
 objective of students unaided synthesis of this compound has 
 not been achieved .
however , we strongly 
 believe that the success of the project described herein is not contingent 
 upon student synthesis of the final target , but , as in many graduate 
 dissertations , the experience gained and growth undergone en route .
a secondary goal guiding 
 module development was to produce a module that could be easily modified 
 and adopted ; this goal was part of the rationale to constrain the 
 activity in such a way as to minimize the logistical issues perceived 
 to be significant obstacles to the widespread adoption of project - based 
 approaches .
it is believed that , with a few modifications , this approach 
 could be useful at other institutions .
for example , although students worked on the project individually , 
 the project is also amenable for small groups of 23 students 
 with division of the workload ; groups working together would also 
 allow a more systematic approach for the exploration of modified reaction 
 conditions .
easily modifiable background documents for various 
 aspects of the project are available for adaptation .
for example , 
 if an instructor would simply like to demonstrate fspe , many modifications 
 of this project could be made to illustrate the technique using commercial 
 reagents or shorter synthetic sequences . although some of these compounds 
 are relatively expensive , costs can be 
 kept low by the use of small scales ( 50 mg ) and grouping students . 

the targeting of strongly colored dye molecules means that only a 
 small amount of product must be obtained to achieve a dramatic visual 
 effect .
the current approach made heavy use of a laboratory 
 microwave to 
 give students practice with another modern , rapidly growing technique .
indeed , the microwave was another tool that 
 students often thought to employ when dealing with the constraints 
 of a traditional 3-h time block for a laboratory session .
fortunately , 
 much of this chemistry was developed outside of the microwave and 
 can also work well in departments without this equipment .
if a microwave 
 is available , a student to microwave ratio of about 6:1 is optimal 
 to minimize bottlenecks in the sharing of this equipment resource . 

although the microwave is equipped to handle multiple samples at a 
 time , if students have proposed different conditions of time and temperature , 
 this can result in a bottleneck .
general laboratory safety procedures , including wearing appropriate 
 personal protective equipment , must be followed at all times .
all 
 organic chemicals involved in these experiments are considered hazardous , 
 and direct physical contact with them should be avoided .
students were required to find 
 the msds sheets of all reagents used and note particular hazards in 
 their laboratory notebooks prior to use of the chemical .
use of aibn 
 ( as in the conversion of 4  5 ) produces 
 nitrogen gas during the course of the reaction , and therefore , precautions 
 need to be taken for pressure build - up if this reagent is used under 
 sealed vessel conditions .
a research module has 
 been developed and successfully implemented 
 in a second - semester introductory organic teaching laboratory for 
 chemistry majors .
key features of the approach were an outlined route 
 to a target that necessarily forced students to think critically about 
 the procedures they planned to use to reach the targeted molecule 
 and to propose modifications to known procedures .
the module exposed 
 students to modern chemistry through the use of microwaves and fluorous 
 techniques , and engaged them in the process of organic chemistry as 
 practiced in many laboratories across the world .
while full details 
 of the project evaluation and assessment will likely be reported upon 
 additional data collection , the initial response to the project from 
 the majority of students has been positive .
although some students 
 resisted the extra work and others struggled with the frustration 
 of  failed  experiments , students generally appreciated 
 the chance to take ownership of their work , as well as the fact that 
 this represented a departure from  canned  experiments . 
 this project or a slight modification thereof can be used to introduce 
 students to authentic organic chemistry practice including modern 
 synthetic techniques and should be easily adaptable to other settings .
 a multi - session research - like module 
 has been developed for use 
 in the undergraduate organic teaching laboratory curriculum . 
 students 
 are tasked with planning and executing the synthesis of a novel fluorous 
 dye molecule and using it to explore a fluorous affinity chromatography 
 separation technique , which is the first implementation of this technique 
 in a teaching laboratory . 
 key elements of the project include gradually 
 introducing students to the use of the chemical literature to facilitate 
 their searching , as well as deliberate constraints designed to force 
 them to think critically about reaction design and optimization in 
 organic chemistry . 
 the project also introduces students to some advanced 
 laboratory practices such as schlenk techniques , degassing of reaction 
 mixtures , affinity chromatography , and microwave - assisted chemistry . 
 
 this provides students a teaching laboratory experience that closely 
 mirrors authentic synthetic organic chemistry practice in laboratories 
 throughout the world . 