Green+synthesis+of+a+fluorescent+natural+product

Solyana Phillips **__Green synthesis of a fluorescent natural product__** The Pechmann condensation: Discovered by the German chemist Hans von Pechmann. Is a synthesis of coumarins via the acid-catalyzed reaction of a phenol with a b-keto ester. The condensation is performed under acidic conditions. The Pechmann condensation experiment will have some positive modification of a chemical process through green chemistry. Dowex 50WX5 will be used as the acid catalyst instead of H2SO4 and POCL3, Dowex it’s easy to handle (the nonvolatile beads make it safer to use). Dowex under solvent-free provides many green chemistry principles to make the experiment without the use of any solvent, thus avoiding the requirement of a rotary evaporator and the use of a volatile solvent as toluene with highly activated phenols such as resorcinol, the reaction can be performed under much milder conditions. This provides a useful route to umbelliferone derivatives.

This Pechmann condensation introduces students to numerous types of organic reactions, Transesterification, electrophilic aromatic substitution, alcohol dehydration and will provide the opportunity to interpret IR and H NMR spectra to help elucidate the structure. Easily observable using a simple handheld long-wave UV lamp, adds attractiveness and potential utility of this experiment.

**Molecular weight:** Resorcinol Molecular weight: 110.11g/mol Ethyl acetoacetate Molecular Weight: 130.14 g/mol 4-Methylumbelliferone Molecular Weight: 176.172 g/mol.
 * % Atom economy**: 176.172 / (130.14+110.11) x 100 = **73%**

**//__Reactants and solvents hazards:__//** -Causes skin irritation Skin corrosion/irritation Category 2. -Causes serious eye irritation serious eye damage/eye irritation Category 2A. -May cause respiratory irritation Specific target organ toxicity, single exposure. -Respiratory tract irritation Category 3. -Acute toxicity (oral, dermal, inhalation), category 4. -Specific Target Organ Toxicity – Single exposure, category 3. - Acute hazard, category1 - Chronic hazard, categories 1,2
 * __Resorcinol__**:

Handled and disposal requirements for wastes: -Personal Protective Equipment dust mask type N95 (US), Eyeshields, Faceshields, Gloves. -Do not empty into drains -Never add water to this product -Take precautionary measures against static discharges -This material and its container must be disposed of in a safe way -To clean the floor and all objects contaminated by this material use ... (to be specified by the manufacturer) -Not recommended for interior use on large surface areas -Dispose of this material and its container to hazardous or special waste collection point -This material and/or its container must be disposed of as hazardous waste -Avoid release to the environment. Refer to special instructions safety data sheet //May cause cancer by inhalation// //Very Toxic to aquatic organisms// //Toxic to aquatic organisms// //Harmful to aquatic organisms// //May cause long-term adverse effects in the aquatic environment// //Toxic to flora// //Toxic to fauna//

-Causes serious eye irritation serious eye damage/eye irritation Category 2A. -May cause respiratory irritation Specific target organ toxicity, single exposure. -Respiratory tract irritation Category 3. -Acute toxicity (oral, dermal, inhalation), category 4. -Specific Target Organ Toxicity – Single exposure, category 3.
 * __Ethyl acetoacetate__**:-Causes skin irritation Skin corrosion/irritation Category 2.

Handled and disposal requirements for wastes: -Equipment Eyeshields, full-face respirator  , Gloves  , multi-purpose combination respirator cartridge.

-Causes skin irritation Skin corrosion/irritation Category 2. -Causes serious eye irritation serious eye damage/eye irritation Category 2A. -May cause respiratory irritation Specific target organ toxicity, single exposure. -Respiratory tract irritation Category 3. -Acute toxicity (oral, dermal, inhalation), category 4. -Specific Target Organ Toxicity – Single exposure, category 3.
 * __Dowex__**:

Handled and disposal requirements for wastes: -Personal Protective Equipment : dust mask type N95 (US), Eyeshields  , Gloves -Do not empty into drains. -Never add water to this product. -Take precautionary measures against static discharges. -This material and its container must be disposed of in a safe way.

-50ml beaker -1ml ethyl acetoacetate -1g dowex -3ml 95% etOH
 * List of equipment and chemicals necessary for the lab: **

(These comments refer to the version that was saved before our lab met, the Friday this assignment was due) Generally good: inclusion of the reaction and some background information causes me to score this report a bit more generously than the other one you prepared for today.
 * __optional/bonus__** :
 * Product# || Name || Price$ ||
 * 00410-100ML || ethyl acetoacetate || 33.50 ||
 * 44473-100G || Dowex 50WX4 || 175.50 ||
 * 459844-500ML || Ethanol || 49.50 ||
 * || total===> || 258.50 ||