Associate Principal Scientist

MSD Malaysia; Rahway (NJ); On-site; USD 142,000 - 224,000; Full time

Benefits offered by this job

Medical, dental, vision benefits

401(k) retirement plan

Paid holidays & vacation

Job summary

Merck's Process Chemistry organization in Rahway, NJ is seeking an Associate Principal Scientist to lead flow chemistry efforts and drive continuous processing for API manufacturing scale-up. The role partners with synthetic/analytical chemists, engineers, and manufacturing teams to advance drug-substance programs from discovery through commercialization.

The candidate will mentor scientists, contribute to publications/patents, and solve complex chemistry and processing challenges with

Qualifications

• Ph.D. in Chemistry or related discipline is required.
• Minimum of 4 years of relevant industrial experience after Ph.D.
• Strong experience in organic synthesis, flow chemistry and continuous processing.

Responsibilities

• Provide scientific leadership for design, development, and optimization of scalable API processes with emphasis on flow chemistry and continuous processing.
• Lead hands-on laboratory experiments in flow chemistry to develop robust transformations and manufacturing processes.
• Influence route design and solve complex chemistry and processing challenges through mechanistic understanding and data-driven decisions.
• Support process characterization, scale-up, technology transfer, and API campaigns across lab, pilot, and manufacturing scales.

Skills

Automation

Chemical Reactors

Flow Chemistry

Flow Cytometry

Innovation

Laboratory Experiments

Organic Chemistry

Organic Synthesis

Production Process Development

Scientific Leadership

Education

PhD in Chemistry or related discipline

Tools

Automation tools

Job description

Job Description Associate Principal Scientist, Process Chemistry The Process Chemistry organization, located at our Rahway, NJ site, is seeking a highly motivated and accomplished scientist with deep expertise in flow chemistry and continuous processing to join the Catalysis and Flow Lab. This position offers an opportunity to play a key role in advancing our pipeline of drug substances, including small molecules, macrocyclic peptides, and bioconjugates, by developing and implementing robust, sustainable, and efficient API manufacturing processes from discovery through commercialization. The successful candidate will lead laboratory experimentation in flow chemistry, develop and implement novel continuous processing technologies, enable new chemical transformations, and influence route design across development programs. The role requires close collaboration with multidisciplinary teams, including synthetic and analytical chemists, chemical engineers, manufacturing partners, and other stakeholders, to support API campaigns at laboratory, pilot, and manufacturing scales. Responsibilities also include solving complex chemistry and processing challenges, supporting technology transfer, mentoring scientists new to the field, and contributing to the external scientific community through publications, patents, presentations, and professional engagement. The ideal candidate will possess strong expertise in synthetic organic chemistry, process development, flow chemistry, and continuous processing, along with the passion and capability to serve as a subject matter expert within the Process Chemistry Department. A proven record of scientific innovation, technical achievement, self-initiative, and effective collaboration in a dynamic team environment is essential. Specific Responsibilities Provide scientific leadership for the design, development, and optimization of scalable API processes across multiple development programs, with a strong emphasis on flow chemistry and continuous processing. Lead hands‑on laboratory experimentation in flow chemistry to develop robust, sustainable, and efficient chemical transformations and manufacturing processes. Influence route design and solve complex chemistry, engineering, and manufacturing challenges through mechanistic understanding, innovative process design, and data‑driven decision‑making. Support process characterization, scale‑up, technology transfer, and API campaigns at laboratory, pilot, and manufacturing scales in collaboration with cross‑functional partners. Mentor scientists and colleagues new to flow chemistry and continuous processing while fostering a culture of scientific excellence, innovation, and collaboration. Contribute to the broader scientific community through publications, patents, presentations, and professional engagement.

Education

Minimum Requirement Ph.D. in Chemistry or a related discipline.

Required Experience and Skills

Minimum of 4 years of relevant industrial experience following completion of a Ph.D., with demonstrated success in small‑molecule process chemistry using flow chemistry. Strong experience in organic synthesis, flow chemistry, and continuous processing, including hands‑on laboratory experimentation in flow. Proven ability to design, develop, and optimize practical, scalable chemical processes through scientific rigor, creativity, and data‑driven problem‑solving. Ability to apply flow chemistry and continuous processing technologies to enable new chemical transformations, influence route design, and address complex process development challenges. Experience with automation approaches for continuous‑flow process development is highly valued. Demonstrated success working across multidisciplinary teams and effectively communicating technical concepts to scientific and non‑scientific audiences. Strong written communication skills, with the ability to prepare clear technical reports, presentations, publications, and documentation. Strong self‑initiative, collaborative mindset, and enthusiasm for serving as a subject matter expert in flow chemistry while mentoring others new to the field. Demonstrated scientific impact through publications, patents, presentations, or participation in the broader scientific community.

Required Skills

• Automation
• Chemical Reactors
• Flow Chemistry
• Flow Cytometry
• Innovation
• Laboratory Experiments
• Organic Chemistry
• Organic Synthesis
• Production Process Development
• Scientific Leadership

US and Puerto Rico Residents Only: Our company is committed to inclusion, ensuring that candidates can engage in a hiring process that exhibits their true capabilities. As an Equal Employment Opportunity Employer, we provide equal opportunities to all employees and applicants for employment and prohibit discrimination on the basis of race, color, age, religion, sex, sexual orientation, gender identity, national origin, protected veteran status, disability status, or other applicable legally protected characteristics. As a federal contractor, we comply with all affirmative action requirements for protected veterans and individuals with disabilities. For more information about personal rights under the U.S. Equal Opportunity Employment laws, visit: EEOC Know Your Rights EEOC GINA Supplement We are proud to be a company that embraces the value of bringing together, talented, and committed people with diverse experiences, perspectives, skills and backgrounds. The fastest way to breakthrough innovation is when people with diverse ideas, broad experiences, backgrounds, and skills come together in an inclusive environment. We encourage our colleagues to respectfully challenge one another’s thinking and approach problems collectively. Learn more about your rights, including under California, Colorado and other US State Acts.

The salary range for this role is $142,400.00 - $224,100.00. This is the lowest to highest salary we in good faith believe we would pay for this role at the time of this posting. An employee’s position within the salary range will be based on several factors including, but not limited to relevant education, qualifications, certifications, experience, skills, geographic location, government requirements, and business or organizational needs.

The successful candidate will be eligible for annual bonus and long‑term incentive, if applicable. We offer a comprehensive package of benefits. Available benefits include medical, dental, vision healthcare and other insurance benefits (for employee and family), retirement benefits, including 401(k), paid holidays, vacation, and compassionate and sick days. More information about benefits is available at https://jobs.merck.com/us/en/compensation-and-benefits.

San Francisco Residents Only: We will consider qualified applicants with arrest and conviction records for employment in compliance with the San Francisco Fair Chance Ordinance.

Los Angeles Residents Only: We will consider for employment all qualified applicants, including those with criminal histories, in a manner consistent with the requirements of applicable state and local laws, including the City of Los Angeles’ Fair Chance Initiative for Hiring Ordinance.

Employee Status: Regular Relocation: No relocation VISA Sponsorship: No Travel Requirements: 10% Flexible Work Arrangements: Not Applicable Shift: 1st - Day Valid Driving License: Yes Hazardous Material(s): N/A

Job Posting End Date: 08/31/2026 *A job posting is effective until 11:59:59PM on the day BEFORE the listed job posting end date.

Our company is a global health care leader with a diversified portfolio of prescription medicines, vaccines and animal health products. The difference between potential and achievement lies in the spark that fuels innovation and inventiveness; this is the space where we have codified our legacy for over a century. Our success is backed by ethical integrity, forward momentum, and an inspiring mission to achieve new milestones in global healthcare.